Contrary to Melee and Ranged weapons, there are no off-hand wands: this role is fulfilled by magical orbs and books. Either can be used with a wand to dual-wield as a mage.
Staves are the two-handed counterpart to wands. Staves cast at Average speed, rather than Fastest, but each hit is stronger. The damage per second is equal between staves and dual-wield, but dual-wielding allows use of the ability Concentrated Blast, while staves offer the ability Sonic Wave.