Ada has six spell options. These are selected by preparing a spell and then selecting the spell you wish to cast (with the appropriate keys). Simply holding down the shoot/cast key causes the standard magic missile to be cast (repeatedly).
You can recognise the currently selected spell by the symbol that flashes in the middle of your spell 窶徙rb窶.
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Blade Barrier. Creates a spinning whorl of blades.
Multimissile. Creates a cluster of four destructive orbs.
Magic Missile. A simple destructive orb.
Wall of Lightning. Casting this spell conjures a slowly advancing wall of deadly lightning.
Blue Sandestin. Casting this spell costs a hit point. The spell conjures a winged blue sandestin that seeks the nearest enemy and attempts to kill it.
Rapid Travel. Select this spell, and hold down the cast key for rapid straight-line travel.