Spontaneous Summoner (3.5e Feat)
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Spontaneous Summoner [General]
When you select this feat, also select one of the following categories: elementals (creatures of the elemental type), celestial creatures (creatures with the celestial template), or fiendish creatures (creatures with the fiendish template). You may use any spell slot to spontaneously cast a summon monster spell of the same level, but that spell may only be used to summon creatures of the selected category.
You can only summon creatures normally available to the spell in question.