Block Wars FAQ v1.1

It's a map-based strategy game where you strive to claim and control territory, competing with other players all over the world. It's available at

You use the cryptocurrency Ether to claim, attack and defend territories. The territories are squares on the world map, or blocks for short. The game is based on the Ethereum block-chain, and is a decentralized application (dApp). And the way to gain blocks is by waging war, and thus the name Block Wars.

There are a few central concepts in the game. You wage war to claim and control blocks on the map. You can claim unowned blocks, fortify blocks you own, attack other players' blocks, move block value between your blocks, boost attacks and defense from adjacent blocks, retreat from blocks, and trade blocks on the Marketplace. Each block has a Block Value (BV) - this is basically the defensive strength of the block when someone attacks it. Block value also boosts your chances of success in battles for adjacent blocks. Fortifying a block increases its block value. Blocks with higher block values are likely to be more valuable on the Marketplace. Each player has Battle Points (BP) - these can be used to claim, attack and fortify instead of sending in Ether from your wallet. You gain battle points when attacking with Ether from your wallet, and when successfully defending a block against attacks. You can also convert Block Value to Battle Points by retreating from a block you own. Battle points can be withdrawn to Ether in a user's wallet. The unit of both Block Value and Battle Points is Ether.

These are explained in more detail below, but here's a list. CLAIM - pay ether (or use battle points) to own a part of the world map, a block. ATTACK - pay ether (or use battle points) to try to take another player's block. FORTIFY - pay ether (or use battle points) raise the defensive value of a block making it harder to attack. MOVE - move block value between adjacent blocks. RETREAT - convert block value to battle points. SELL - offer a block on the marketplace. BUY - buy a block that is for sale on the marketplace. Those are the game commands associated with blocks. A user can also WITHDRAW - convert battle points to Ether.

The defensive strength of a block in Ether.

A player's available in-game resources. They can be used instead of Ether to claim, attack or fortify blocks. They can also be withdrawn from the game as Ether.

The game is decentralized, open, borderless, and censorship-resistant, just like the Ethereum blockchain it’s built upon. Anyone can join. No need to register a user. Just go to the map, claim a block, and you’re participating in Block Wars. You can provide an uploaded image, username, tag, and homepage URL. Only the first two are mandatory. All these settings can be changed later, at any time. Your uploaded image will be displayed on your blocks to show they are yours, and your username will appear in toplists and leaderboards. The thing uniquely identifying you in the game is your public Ethereum address.

We love those games and some features were inspired by them, but this game is its own. Block Wars is NOT an idle game or a pyramid game or a gambling game. We want it to be a simple, but deep, strategy game. Show us your best strategic thinking!

If you play with a solid strategy, yes. If you can gain more battle points than the amount of Ether you've put into the game, you can then withdraw the battle points (earning Ether). You gain battle points by successfully defending against attacks, or by successfully attacking other players' blocks and converting their block value into battle points using the RETREAT command. You can also make Ether by selling blocks you own to other players. A highly coveted block, like central Tokyo, might become valuable. Also, if you want to do clever high-profile marketing of your logo by skillful use of the block image feature. Maybe you have a company, blog, YouTube channel, other Ethereum dApp or something similar that would benefit from some creatively designed exposure?

Yes. We charge a 5% commission on all battle point withdrawals.

Yes. We charge a 5% commission on all marketplace transactions.

Yes. We charge a 5% fee on attacks, and a 5% fee on retreats.

Yes. We need to find the right game economy balance and it's too cumbersome to re-deploy updated contracts every single time we want to tweak a fee parameter. We won't raise fees.

True, though we as creators see these fees as a fair way to get something back for all the time we've spent building this game for your enjoyment. We feel this is a more transparent and credible approach than doing a token sale.

Absolutely. Wars are not won idly standing by while chewing on a stalk of wheat! If you want your claim to fortune, you better be prepared to fight for it. In this game, you do that by spending Ether to claim, conquer and fortify territory in the form of blocks. If you can’t stand the sight of blood, you can also search for blocks that are for sale, and accept those offers to peacefully purchase a block. Either way, claiming, fortifying, attacking or buying blocks will all cost you Ether, that gets converted into block value or battle points depending on the command.

You need to use some kind of Ethereum-aware browser or browser plugin, in order to sign Ether transactions when making moves in the game. The most commonly used one is Metamask, a Chrome and Brave browser plugin - we have mainly tested and verified the game using Chrome and Metamask, there may be issues on other combinations. The game runs best on a screen with a resolution of 1440 x 900 or higher. Mobiles aren't supported. Brave, Mozilla Firefox and other browsers should work but we haven’t spent significant time testing on them. We recommend using Chrome and Metamask.

The game looks best with a 256x256 image (jpg, png) that has a transparent background. We'll scale it for you if in another format, but please use pictures of 400 kB or less. Here's an example:

When you change your image, it will change for all your blocks regardless of when you claimed them. A user can never have multiple active images at the same time.

You go to the Block Wars world map and search for the location you want to claim. Click on one or more map blocks at that location, then click the "Claim" button. A dialogue will appear where you choose the amount of Ether to claim with, and submit the transaction. You can choose to claim with Ether from your wallet, or with your Battle Points. Once sent, you must wait for the next Ethereum block to be mined. If all goes well, the territory is then yours and your image will be displayed on it as a sign of ownership! The block value of the block will be the amount you sent.

Multiple game moves may happen in the same Ethereum block. Since all moves (transactions) in a block get mined at the same time, moves executed prior to yours may affect the outcome of a move you make. This is normal and expected, and inherent in running on Ethereum.

The minimum unit of value in the game is 1 finney (0.001 Ether). To claim a block, you must send at least 5 finney = 0.005 Ether. You must send at least 1 finney when attacking, fortifying, accepting offers or doing any other game move that requires sending Ether.

Make sure you’re using Metamask or another Ethereum-aware browser. Make sure Metamask hasn't crashed - it happens. If so restart the plugin in Chrome.

Yes, you can try. However, already-claimed blocks will be more expensive to claim, since you must attack them. In fact, the more popular a particular block is, the higher its block value is likely to be, and the more Ether will be required to successfully attack it to make it yours.

You click on the block on the map. The block must be owned by another player. A dialogue will appear where you can enter your attack value (in Ether). You can choose to attack with Ether from your wallet, or with your Battle Points. The boosted attack value must be within 10-1000% of the boosted block value. Then click Attack. The minimum attack amount is 1 finney = 0.001 Ether. You will need to authorize the transaction e.g. using Metamask.

No. This is war, remember? Whenever a player wants to claim an already-claimed block, battle ensues. This kind of claim is called an 'attack'. The odds are based on offense = the amount of Ether or Battle Points the attacker stakes, vs defense = the current block value of the block. You improve your odds by attacking with a higher amount than the defender is defending with. You improve your odds even further by gaining a boost from adjacent tiles that you own - but this is also true for the defender! No attack is ever 100% certain, and you can't go beyond direct odds of min 9.1% or max 90.9%. This way, a highly fortified block with a high block value, and surrounded by boosting blocks, becomes virtually impregnable to attacks from small fry!

Of course. Owning adjacent blocks to the one you attack will give you an attack boost (marked by red arrows on the map when you attack), while the defender will get a boost from their adjacent blocks (marked by blue arrows on the map when you attack). Just like in real battles, surrounding or flanking the enemy is a good strategy. Increasing your attack amount or fortifying to raise block value also increases your chances.

No. For the case of blocks that have a previous claimer, you must attack and conquer them one by one. But you can send multiple attack moves as parallel transactions.

Yes. That's why it's called Block WARS. No claim is safe forever. Check in frequently to make sure your ambitions of world domination are on track.

Well, you can defend your claim to existing blocks by adding Ether or Battle Points to your claim for those blocks, or “fortifying” them. That increases their block value, makes them more costly to attack for other players, and thus increases your chances of defending them against attacks. You can also claim adjacent blocks to take advantage of their boost to your defense against attacks.

Yes. The attacks will resolve in the same order they are mined in the next Ethereum block, which is outside the players’ control. If your moves take a long time, try increasing the gas price a bit.

No, you will still attack the block. But your attack might not be aimed at the player you thought, and the chances of winning might have changed. Just like in real battles, circumstances change quickly. Be ever watchful.

You click on the block on the map. The block must be owned by you. A dialogue will appear where you can enter your fortify value, in Ether or Battle Points. Then click Fortify. The minimum fortify amount is 1 finney = 0.001 Ether. You will need to authorize the transaction e.g. using Metamask. The block value will increase with the amount you specified.

Yes. Block value can be moved to an adjacent block you own, or converted into Battle Points using the Retreat command. You can even move or retreat all the block value, and then you lose your claim to the block you moved them out of. This feature, combined with boosting attack and defense from adjacent blocks, allow for quite some interesting strategies.

Isn't it? Yes, you can, to any adjacent block you own. This feature, combined with boosting attack and defense from adjacent blocks, allow for quite some interesting strategies. Think RISK, think Go.

No. Moving block value automatically cancels any open for sale offers for both the source and destination blocks, to avoid exactly that kind of thing. Make (block) war, not sneaky trades.

Click on a block you own. Click Move. You will see blue arrows appear for all adjacent blocks you own, and their current block values. In the Move dialog, a small 3x3 direction selector will appear. Use the selector to choose the direction to move in (don't click on the map to choose the direction). Click Move again and confirm the move using e.g. Metamask.

Click on a block you own. Choose the amount of block value you want to convert into Battle Points, then click Retreat. You must either leave behind at least 5 finney = 0.005 Ether, or you can retreat ALL the block value, in which case you will lose your claim to the block. Confirm the retreat using e.g. Metamask.

Battle points can be very useful when attacking or fortifying other blocks, since you can use them instead of Ether from your wallet for these commands. Also, if you ever would want to withdraw Ether from Block Wars, the way to do that is to convert Battle Points to Ether, so you may want to maximize your Battle Points before withdrawing in that case. Two good reasons.

Its block value remains unchanged. But the amount you attacked with will be converted into battle points for the defender (if it makes you feel better, you can imagine all your attacking troops deserting and joining the other side since it was obviously superior).

Its block value remains unchanged, but it is now yours, and your attack amount (if from your wallet) is now converted to Battle Points! (You can imagine all the people living there rejoicing and welcoming their new, powerful ruler).

A conqueror should always be a bit paranoid. Of course you might be. They're out for your blood! It is often prudent to rapidly Fortify a block you have conquered in battle to increase your chance of holding onto it (see it as telling your victorious troops to rebuild the walls immediately rather than just celebrate and pillage).

There is no way to give away blocks for free. By using the Marketplace mode, you can offer a block up for sale. You can set any price you like, but never less than one finney (0.001 Ether). Another player can then accept your offer, which will transfer ownership of the block to them.

Click on the Marketplace $ icon (top right corner) to go into Marketplace mode. Then click on one of your own blocks on the map. A dialogue will appear where you can enter your requested price. Then click “Sell”.

In Marketplace mode, click on one of your blocks on the map that is already for sale. In the dialogue that appears, enter a new offer price and click Update.

In Marketplace mode, click on one of your blocks on the map. In the dialogue that appears, click “Unlist”. The block will no longer be for sale and will no longer appear on the marketplace.

Go to Marketplace mode by clicking the “$” button in the top right corner to toggle between the Battle mode and the Marketplace mode. In Marketplace mode, you will see a list of blocks for sale instead of the normal event feed and toplist.

Sure. Click the fire icon button in the top right corner to toggle a heat map overlay on and off. Green means low values, yellow medium, and red high values. This overlay works in both Battle and Marketplace mode.

In Marketplace mode, click on the block you want to purchase on the map, or in the Blocks for Sale list to the right. The block must be owned by another player. A dialogue will appear where you can accept the offer. The purchase amount will be pre-filled for you to the requested amount. Click Buy. You will need to authorize the transaction e.g. using Metamask. The block will become yours, and the seller will receive the purchase amount in their Ethereum address.

We charge a 5% commission fee for Marketplace trades.

Nothing. The block value remains unaffected by the sale. The only way to increase block value is by fortifying.

You can enable a heat map view by clicking the fire icon in the top right. The heat map will indicate where high-value blocks are located. Click the icon again to turn the heat map view off. This works both in Battle and Marketplace modes.

No. A block is a location on the game map that can be claimed, attacked, fortified, or traded between players. Without blocks there wouldn’t be any Block Wars game - they’re intrinsic to the game itself. Owning a block does not give the owner voting rights, a share in a company, a share of future earnings, dividends, or any other security-like value. A better analogy would be e.g. comparing owning tokens to owning Magic the Gathering™ cards. Owning them is necessary in order to play the game - they constitute the game - and they can be traded peer-to-peer between players.

Not really. Once you own a block, you don’t further use it as a means of paying for, or getting access to, something else except boosting attacks or defenses on adjacent blocks which is an intrinsic part of Block Wars strategy. Claiming and conquering the blocks themselves in a skillful way is what Block Wars is all about!

Your image will be displayed on all your blocks, to show all the world that they're yours. This is your path to fame, glory and renown as you dominate Block Wars and rise to the top of the leaderboard and conquer the world map! And let’s be honest, it is quite satisfying to conquer your hometown from a pesky friend and show them who’s the boss. You can choose to offer your blocks for sale on the marketplace, to allow more peace-oriented players a chance to own them without bloodshed. You can fortify them, to increase your chances of successfully defending against attacks. And you can use the block to boost further attacks, moving block value around to where it maximizes your boost in future moves, or retreating when circumstances dictate it. Strategy, my friend, is what underlies the Art of Block Wars. And, some blocks may contain surprises...

Let's just say that there may be benefits associated with owning certain blocks at certain times. Stay tuned to our Discord: for more information.

Of course. The illustrious few who climb to the pinnacles of Block Wars will bask in the glory of being visible on the global toplist. By default it shows the players with the highest amount of total block value owned. There are some other views available, check the toplist drop-down for options.

Sure. Click on the block and click the History tab in the block info dialog, and you will see a timeline of previous claimers and other events that has happened to the block in the past.

It's a Chrome and Brave browser plugin that lets you sign Ethereum transactions, sending Ether to someone else - in this case to Block Wars. If you don't have it, go to and follow the instructions. The game has been tested using Metamask in Chrome.

It’s a web browser that’s natively aware of Ethereum, and that can be used to sign Ethereum transactions. If you want to use it, you can download it at NOTE: The game has not been significantly tested using Mist.

It’s a web browser that’s privacy-oriented, and that works with Metamask. If you want to use it, you can download it at You will also need to install the Metamask plugin when using Brave. NOTE: The game has not been significantly tested using Brave.

Cipher is a mobile browser that’s natively Ethereum-aware, much like Mist, that can be used to sign Ethereum transactions. If you want to use it, you can download it at NOTE: The game has not been significantly tested using Cipher, and the game is currently not designed for mobile screen sizes.

No. To play, you must first transfer some Ether to your Ethereum account, where you can access it using e.g. Metamask to send and receive Ether.

The back-end logic resides in a set of smart contracts on the public Ethereum blockchain. We use EthJS to interface the contract from the browser, and players use e.g. Metamask for signing transactions. We use a mix of Superblocks Studio and Truffle with ganache-cli for building, unit testing and deploying. We store user images on IPFS.

Well, since this is a decentralized application, anyone can claim a block. They don't even need to use our game web page; they can invoke the smart contract functions directly e.g. from a custom-made program. That's the 'permissionless, open' part, and that's ok - we can't prevent anyone from doing so though of course the idea is to play using our web site. Note that anyone accessing our smart contracts, whether through our web site or directly, is thereby accepting our Terms of Use (see top right menu for the latest version). The contract enforces the rules of the game mechanics, but is not a legal contract. That said, if you should find exploits or bugs, please be nice, put on your white hat, and let us know before exploiting or publicly announcing them so we can fix them!

Our long-term goal is to make it 100% decentralized. This way of developing is still very immature, though. For example, we planned to use IPFS for all web pages. Turns out this wasn't trivial for dynamically loaded content, so we ended up using it only for user images, and using Google Firebase for serving the rest of our web content. We’re using Google maps, because there isn’t any truly decentralized map initiative. There are open source ones, like Open Street Map; however, we chose Google Maps because it’s the one users are more familiar with. We store the game state on-chain, and rely heavily on Solidity events to reduce the need for having too much mutable on-chain state. We're constantly trying to optimize this trade-off for a good game experience, having the lowest gas costs possible, and having as high a decentralization as possible.

Sure. The game consists of five main smart contracts, and can be found here using BW: 0x6a20d74106f28ad19c60115917ff363ad71f525f, BWMarket: 0x0cd7107299fb0b4c7d4b89f48b638d6c814d99a1, BWService: 0x168848b7ec6c61bd452ee6e74ae85b07cc3b8d17, BWData: 0x53d34d53a692e6352565909acda5af9145f11bf6, BWUtility: 0xc6ee4b2ae64b4d506362f25886b806809b8e5beb. Please help us improve and let us know of any issues or exploits you might find in them!

That's right. We're doing this for fun, in our spare time, to learn more about Ethereum, get a better understanding of UX using Metamask in gaming, and to provide a nice game for Ethereum owners. So we built in safety mechanisms, and we as owners can withdraw fees at any time. Block value and battle points, however, belong to the players and the owners can't withdraw them.

In theory, nothing. In practice, that function would only be used in case of a MAJOR problem (e.g. a security flaw that allows an attacker to steal other players' funds) that can't be fixed even by pausing the game, and if we ever have to use it we'll distribute block value and battle points among the users afterwards. It's a trade-off between true decentralization and being able to act if something goes terribly wrong. You'll need to trust the owners to do the right thing. We will.

It’s a safety mechanism in case users upload offensive images. The owners can flag such users as censored. Censored users will get a default "NSFW" image displayed in the map view. The owners reserve all rights to decide what’s eligible for censoring or not, but we’re pretty open-minded… Just use your common sense and everything should be fine.

We know. The game move speed is inherently limited by the block mining speed of Ethereum. As for signing every move with Metamask, unfortunately this is how Ethereum works at the moment, and there’s currently no way around it. We hope to see future Ethereum developments where one can pre-delegate spending authorization of Ether e.g. to pre-loaded funds in a smart contract, to avoid confirming every single transaction in this fashion and instead be able to pre-pay playing the game - however this would surely expose a whole new bag of security risks. You’ll have to ask Vitalik Buterin about that ( Right now this is how it is and one of our goals with building the game has been to explore the usability of an on-chain Ethereum game given how Ethereum, gas, transaction signing of state updates and block mining times work. We may also explore using other technologies in the future and deploy the game on them if they offer significantly faster transactions (HashGraph is one we're interested in for example).

Yes. We charge 5% commission fees on attacks, retreats, sales and withdrawing battle points to Ether. Block value belongs to users, and can be converted to Battle points. Battle points can only be withdrawn by users, not by the creators. If this game becomes massively popular maybe we'll make some money off of it. Funds we might choose to withdraw will mainly go towards improving the game in the future, make new games, and helping the Swedish and global Ethereum community. This game was born out of the Swedish Decentralized Camp meetup ( On the other hand, you can play the game without having to participate in an ICO. :)

This is a game that's driven by Ether. There's no need for an ICO. Didn't you read the previous answer?

Block Wars is et(h)ernal, with the players vying for global conquest. One way to win would be to conquer the entire planet, but even then other players could attack you. You should try out different strategies and see which works best for you. And meanwhile, make sure to have fun and earn some et(h)ernal glory!

We're not confident enough that we've created the perfect, eternal, bug-free version of this game right from the start. We have seen examples in the past where bugs have caused major problems in contracts that had gone through multiple security audits, e.g. TheDAO, Parity Wallet to name two high-profile examples. If this happens, we'll pause the game - it has a global pause switch we as owners can set, designed just for this kind of situation - read all the game data from the contract, create a new version that fixes the problem, import all the game data into the new contract, and then restart the game on the new version, on a new contract address. The old version will be self-destructed once we're confident the new version works. We have also separated stateful and stateless contracts, so we can update game rules without having to modify game state by re-deploying only the stateless contracts.

See the answer for how we will handle really nasty bugs.

That's our ambition, yes. The first version of Block Wars is a deceptively simple game that actually has significant strategic depth, but we have the ambition to produce future games with more advanced game mechanics, variations of the rules of engagement, and different game economies. Maybe we'll make time-limited tournament versions for specific events. And of course we're more than open to feature suggestions from our users!

Multiple players making moves in the same block can cause this. E.g. if you want to move block value from block A to block B, but another player attacks and takes block B from you before your move is executed, your transaction would be reverted since you can't move to a block you don't own. In any such cases, you won't lose your sent Ether, just some gas. We've tried to minimize your gas loss in these situations by using require() heavily to check for error preconditions in our smart contracts. In case the problem persists, try refreshing the game web page to make sure your map is updated to current game status.

Use The lower the value you use, the bigger the risk that your move won't be mined in the next Ethereum block and vice versa. If you want save money (but risk having to wait longer) use the SafeLow value, otherwise go with standard or even higher to speed up moves as much as possible.

Join our Telegram channel:, or our Discord: Most of us also hang out in the #blockwars channel of the Decentralized Camp Slack. More info on how to join can be found here:

Why not use a CryptoKitten? They're cats, they're cute, they have claws, they're decentralized. Go visit and once you have a beautiful, rare kitten, you can let it conquer the entire planet!