Here is the full list of all 35 Teratopia achievements.
Unlock the 3 races
Pull down the Big Wall
Have 20 minions on the battlefield
Grab 15 chests
Kill 50 enemies with Belly Blow
Have a minion of each class on the battlefield
Combine two powers
Only feed enemies to the carnivorous plant
Kill 5 ghost Katoos
Kill 25 enemies with turrets
Kill 50 enemies with strong attack
Kill 2 Elite enemies using Monstrocity
Feed 20 carrots to the engineers
Equip a costume
Defeat the baby
Defeat the mom
Defeat the punk brother
Defeat the hippie brother
Defeat the sister
Defeat the grandpa
Defeat the gardener
Defeat the witch
Defeat the sailor
Defeat the grandma
Achieve maximum minions capacity
Reach level 50
Spend 1000 eyes
Buy all avatar costumes
Use an Engineer against Punko and Hippie-Bro
Complete the Teratopedia
Defeat the three aunts with a double damage costume
Protect the 3 Grandfarter's tombstones
Kill all the guards in the Ancient's castle
Defeat the Ragon
Complete all achievements