Summon Spirit

Upon casting this spell, a malevolent spirit in the form of a wraith is called to serve the caster for 1 turn per level. If the caster is 10th level they may choose between 1d4 wraiths or one spectre. At 15th level the caster may opt to summon 2d4 wraiths, 1d3 spectres, or one ghost. The summoned spirits will serve according to its ability, usually by combating the caster's foes, and generally disappearing at the end of the spell's duration. Occasionally the spirit does not depart at the end of the spell duration, but simply becomes free of the compulsion to serve and will usually attack the caster. The chance is 5% for any particular wraith, 10% for spectres, and 20% for a ghost. When this occurs, the spirit will remain in the area for a number of rounds equal to the caster's level before departing. A spirit with less than half its hit points will not stay regardless. The caster would be wise to have protections or other contingencies against the rogue spirits.