Maya/Skill tree

Motion
The Siren's Motion Tree focuses on crowd control and defenses: reflect enemy bullets; disrupt multiple enemies at once; brainwash bad guys into fighting for you!

Harmony
This tree is focused on healing.

Cataclysm
This tree is focused on elemental effects.

Visit http://www.borderlands2.com/us/skilltree/siren.html for skill trees.