Elder Scrolls IV: Oblivion - Shivering Isles

You don't need to be mad to quest here, but it helps

And what role-playing expansion would be complete without a fresh menagerie of monsters - and weapons to repeatedly hit them round the head with? As with the art style and demeanour of the locals, creatures differ according to which subsection of insanity you’re adventuring in. A typical beast found in the over-the-top lands of Mania, for example, is the Elytra - a giant ant-like insect with garish oil-spill rainbow patterning, beady red eyes and furiously jabbing pincers.

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