Here is the full list of all 22 Supernova Tactics Playtest achievements.
Beat Normal Difficulty
Beat Hard Difficulty
Beat Impossible Difficulty
Crystals Unlock Upgrades
Beat Round 24 (Normal)
Beat Round 49 (Normal)
Beat Round 74 (Normal)
Beat Round 99 (Normal)
Beat Round 24 (Hard)
Beat Round 49 (Hard)
Beat Round 74 (Hard)
Beat Round 99 (Hard)
Beat Round 24 (Impossible)
Beat Round 49 (Impossible)
Beat Round 74 (Impossible)
Beat Round 99 (Impossible)
Beat Normal Masochist
Beat Hard Masochist
Beat Impossible Masochist