Here is the full list of all 21 Viktaram achievements.
Beat the game
Beat the game with full health
Collect all Stars and beat the game
Collect 100 coins and beat the game
kill9
kill10
kill7
kill8
kill6
kill5
Pickup a star
kill4
kill2
jump
Pickup a heart
Break a box
kill1
kill3
Take your first steps
Pickup a coin
attack