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