It's called the sewer-golem to be correct.
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If you talk/help the guy in the glass container (you'll get an energy cell after that) there's a table within his room. On that table is a stone of some kind. That's the stone to activate the sewer golem. Hope this helps.'
Ow yeh, and er..Welcome
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There's something in your eyes, ah no, I see now, it's the reflection of my deadly gaze - Mirac Honorguard
(Necromancer)
You deal, I'll cut -- Lilarcor