Ultravision is relevant for Clerics mostly because they don't have an easy source of it other then Guise for a little while longer.
Hide - Undead may see through it, but the amount of times you avoid pulling sit aggro in groups is freaking awesome on some classes, cleric being numero uno for that purpose.
Humans get a far better aggregate though. Both races are Robers, so all the special Cleric robes both can get.
Natural Dark Elves are the only Clerics who get Hide and Robes ;D
Worshipping Innoruuk and being super Evil though is rough on them without invis.
Human Clerics get so many cool items at Paineel tho
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