Here is the full list of all 10 Hexane Playtest achievements.
Kill 10 Players Kill 10 online players (can be the same player)
Kill an online player
Join an online player
Kill 100 NPCs
Kill 50 NPCs
Create amazing photos in the photomode!
Kill 10 NPCs
Kill your first NPC
"Well done, you got the lead developer! Have fun killing other players :3"
"I dont much like the tone of your voice"