Issue 1244 (http://www.adom.de/forums/project.php?issueid=1244) states that Orb Guardian corpses were buffed. Recently this buff (constant +stat boosts from them) seems to be reverted, and they are useless again (and maybe even more, given amount of corruption).

I think that this was done accidentally, and this corpses should be reverted to their previous behavior.

Tested on - Ancient Chaos Wyrm corpse.