Shantae can can learn multiple transformations, each of which gives her different abilities and allows her to access new areas and items. She learns them from Guardian Genies and Magic Fountains, both of which are found in the games' dungeons (with the exception of the Elephant form in Risky's Revenge, which is in the Forest Cave).
Does this count as a form? The manual thinks so. This form allows Shantae to...be herself. She can use magic attacks as well as her regular hair whip attack. She's also capable of swimming, but not too deeply, and crawling slowly through low spaces. Girl form's greatest advantage over the other forms is combat - she has access to more moves and magic powers in this form as compared to others.
MonkeyEditShantae (GBC) (Dribble Fountain) and Shantae: Risky's Revenge (Squid Baron's Labyrinth). It is a small, fast form that allows her to climb walls and perform wall jumps, and move quickly through narrow passages. When the monkey touches a wall while in mid-air, she can be made to climb it by pressing up or down, or wall jump off of it (). The ). The pressing or and releasing), which functions as both an attack and a way to reach new areas. The dance sequence in Shantae is , and in Risky's Revenge it's dance pose #1.
ElephantEditGolem Mine) and Shantae: Risky's Revenge (Tangle Forest Cave). The elephant is large, slow moving, and can barely jump, but her charge can instantly destroy certain rocks, walls, and creatures (such as Stone Golems). It is the only normal form to come with an attack. The +). The dance sequence in Shantae is , and in Risky's Revenge it's dance pose #2.
SpiderEditCackle Mound). Like the Monkey she is small and can climb surfaces, however unlike the monkey she climbs surfaces in the background rather than walls in the foreground. .
HarpyEditTwinkle Palace). She can fly through the air (tap ), allowing access to all remaining areas, but cannot crouch or crawl. The ). The dance sequence is .
The Tinkerbat is an optional 'secret' form in Shantae (GBC) (Advanced Genies! (500 gems) in Bandit Town, available only on Gameboy Advance). She (presumably all Shantae's forms are female, including this odd one) can climb on walls and background surfaces, wall jump, and charge with a battering ram (by pressing +), combining functionality of the Monkey, Spider, and Elephant. She also has a cutlass which swings in a wide arc, attacking enemies above and below. She also has an amusing run animation that suggests insane panic. Because of her variety of abilities, the Tinkerbat is the best general-purpose form and is highly recommended as it reduces the amount of transformation during exploration. The main drawback is that despite her small size, the Tinkerbat cannot crawl through narrow spaces, requiring the player to revert back to Shantae form every so often. The dance sequence is .
MermaidEditThe Mermaid is the third and final form she acquires in Shantae: Risky's Revenge (Hypno Tower). She can swim () deeper than Shantae, who floats to the surface in water. With the ). The dance pose is #3.