Crawl Monster Info

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Henzell says...

An {orb of energy} with double refund rate. Has a 40% chance to refund spells you cast and 100% chance to refund spells you miscast. Djinni are ineligible for the refund and the -wiz. In 0.34 it's has normal refund rate but when it refunds MP it can additionally apply antimagic to monsters you can see and refund additional MP for every effected monster.
Before 0.30, an unrandart +9 {magical staff} that refunds the MP of a cast spell with a chance of evocations_skill / 81, maxing out at 33% with 27 Evocations. If successful, it also has a chance to cause either 2-5 turns of confusion or 1-5 int drain. The chance of this is 1 / (evocations_skill - spell_mp_cost).
Prior to 0.26, you had to evoke for {channeling} MP, but it sometimes failed and instead gave miscasts curiously similar to the old and non-existent {divination miscast}s. Like {crystal ball of energy}, the success chance increased with evocations, but unlike CBoE, this chance did not depend on current MP, hence it could be used at 0 MP.
see {channeling}
see {wucad_mu's_monastery}