"What can make a game to be a great game, apart from game design and gameplay is the animation of the sprites. If you played computer games in stone age, you will surely remember the first Prince of Persia. It was a fair platform game, but the animation of the captive prince was awesome in 1989 – and it still rocks anyway – and made the game fly to worldwide success.
While I can’t teach you how to create wonderful sprite animations – my graphic skills are around “3 years old baby” level – I can show you how to manage animations in your HTML5 games with Phaser."