Ring of the Archmage (3.5e Equipment)
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Ring of the Archmage: A wizard wearing this ring gains one bonus spell slot for each spell level, starting from level 0 up to level 9. The wizard must wear the ring the entire time spent resting and preparing his spells to gain any benefit from this item. If the ring is removed, the bonus spells slots are lost until the ring is worn again for 48 hours.
Strong Universal;CL 20; Forge Ring, caster must be able to cast 9th level wizard spells; Cost 99,925 gp and 7,994 XP; Weight: — lb.; Market Price: 199,850 gp