Identify a green shard spell in Magicka
I believe the spell you are looking for is Ice AoE cast, possibly with a life thrown in for the green color. This shows ice-looking shards spike up from the earth all around you, dealing a fair amount of AoE damage, enough to outdamage a single Life added to give it a green color.
Screenshot of 5xIce AoE cast [QRQRQRQRQR]
Sounds like Life + Ice + Direct target (i.e., Right click, not shift right click. It's not technically an area spell, though it does fire in a frontal cone) - be careful, those shards actually HEAL non-undead targets.
Here's a pretty picture for you: