Ring of Summoning Affinity (Agathion)

This ring is forged from electrum and inlaid with runes. If the wearer can cast summon monster spells, the wearer adds silvanshee to the 3rd-level list of monsters she can summon with those spells, adds vulpinal to the 5th-level list, adds avoral to the 7th-level list, and adds leonal to the 8th-level list. Also, once per day on command the wearer can use this ring to summon a silvanshee, as if by the summon monster III spell.