Most of the forms you get by just progressing through the game. It is impossible to get this achievement on the first playthrough before you finished the
Hypno Baron's Castle level when you get your last dance (dance = form). This guide is for first time players (story mode, not hero mode), If you play hero mode you have most of the dances (monkey, crab, elephant, harpy, mouse) unlocked by default and only need to pick up the rest for the achievement. There are 12 slots but 15 dances. The forms / dances are listed in the order you can obtain them:
1. Monkey form: after clearing
Main Street and beating
you'll get it automatically. If you want to get the Bat form as early as possible, then replay Main Street right away with the Monkey form and when you need to go down on several steps in a zig zag - enemies jumping out of barrels on every corner - instead of going down scale the right wall on the top with the jugs and go in the portal on the other side and get the monkey bullet upgrade.
2 (or last). Bat form: in
Mermaid Falls Factory when you move higher and higher in the factory by grabbing moving rings, you need to get to the upper left corner of the map. Easy to find if you do the following: every time you can touch the left wall try to scale it with the monkey as high as you can. If there is a platform with enemies above you and you can't go further then you are still need to get higher by rings and try there. If you have the monkey bullet ability you can jump between walls and get the bat right away. If you don't then come back when you have the Harpy dance.
3,4,5,6,7,8,9: At the end of
Mermaid Falls Factory you'll meet a snake lady called Tuki. She is pretty much impossible to miss, just hit her pot and she will sell you forms:
- Warp (200)
- Revive (250)
- Super Revive (500)
- Obliterate (300)
- Dryad (100)
- Blobfish (can be traded for Obliteration and back for free) - you must trade it at least once
- Gemjug (can be Traded for Warp and back for free) - you must trade it at least once
These forms can be bought at any time either by coming back or meeting Tuki on another level.
10. Crab form: after clearing
Mermaid Falls and beating
you'll get it automatically.
11. Elephant form: after clearing
Tassel Town and beating
you'll get it automatically.
12. Mermaid form: Go back to
Mermaid Falls. There is a warp gate on the rightmost side of the falls (not in the factory) with a giant block inside. Headbutt it in elephant form and get the Mermaid form form the chest.
13. Mouse form: After clearing
Cape Crustacean and beating
you'll get it automatically.
14. Spider form: Go back to
Tassel Town. Around the middle of the first part (sand dunes, not in the tower) you'll see a warp door in the middle of the road. Go in, turn into Elephant and when the wind tries to blow you away, headbutt your way towards the other door. Pick up the Spider form from the chest.
15. Harpy form: after clearing
Hypno Baron's Castle and beating
you'll get it automatically.