You're Dust, a mysterious being without memories of his past. While you fight your way through monsters, you'll eventually discover what you are, where you came from and where your path will lead you.
Will you be a righteous soul or an evil spirit?
Okay, you won't make any big choices throughout the game, so ignore the last sentence, i just liked the sound of it ^^
"Dust - An Elysian Tail" is best described as an action-rpg-platformer i guess.
You'll jump and fight your way through monsters with your sword through multiple levels, gain new abilities while you progress and level yourself up while finding/and or crafting (which is kept very simple) new gear to make you even stronger.
The graphics are beautifully drawn and very colourful. The 2 main characters, Dust and Fidget, his sidekick, are pretty memorable and their dialogues have some decent humor in it.
I really enjoyed it and would recommend you'd give it a try, if you like this sort of genre.