Elemental Affinity | Divinity Original Sin Wiki

Elemental Affinity is a Talent in Divinity: Original Sin Enhanced Edition. 

Elemental Affinity

• Lowers the Action Point cost of spells by 1 when standing in a surface of the same element.
• Standing in water or on ice affects Hydrosophist skills.
• Standing in fire affects Pyrokinetic skills.
• Standing in ooze or oil affects Geomancer skills.
• Standing in electrified water affects Aerothurge skills. (Consider taking Lightning Rod for stun immunity.)
• Standing in blood affects Witchcraft skills.