Lightning - at level two is actually Chain Lighting and it can hit up to five units.
Gift - refreshes abilities of the target unit. I usually cast it on Inquisitors to res those units (evil beholders and archmages) that I can't use my Resurrection spell on . My Res spell is only lvl 2 so it can be cast only on 1-3 lvl of units, but the Res skill of Inquisitors has no such limitation.
Blind - makes an enemy unit lose 2 turns (no moving, no attacking).
Hypnotize - take control of an enemy unit for 2 turns. It usually ends with all the enemy units concentrating fire on the hypnotized one, since it is the closest to them.