Here is the full list of all 13 Oh No! Bugs! achievements.
Kill 100 Bugs
Kill 50 Bugs
Kill 10 Bugs
Get A 5 Kill Combo
Kill 250 Bugs
Kill 500 Bugs
Buy Every Shop Item
Buy The Buggy From The Shop
Buy The Dozey From The Shop
Buy The Hovery From The Shop
Buy The Spidey From The Shop
Reach Max Lvl
Get A 10 Kill Combo