The Ethereum Development Community recently published a guide on creating Phaser games running on the blockchain:
"In this tutorial, we will be creating a simple 2D arcade-style game where highscores are recorded in a smart contract on the Ethereum blockchain. We will guide you through setting up the project, programming the game using Phaser.js, writing the smart contract in the Solidity language using the Remix IDE, deploying the smart contract to Ethereum testnet, and finally connecting our game to Ethereum using MetaMask and Web3.js.
What kind of game are we making? We’ll keep it simple. The screen will have a bunch of randomly placed coins, and the player must collect as many of them as they can before the timer runs out. The score will then be recorded in the smart contract.
This tutorial will give you a great introduction to Ethereum Game Development. This guide will require you to have basic Javascript understanding.
If you don’t know basic Javascript and want to learn Ethereum Game Programming for real we recommend taking “Blockchain Game Developer” track in Ivan on Tech Academy.
The academy will teach you everything from scratch – no prior programming knowledge needed."