Drana (Aion)  

Aion Wikibase™ Dictionary

Drana is a form of negative Aether, sometimes called "anti-aether", and is the energy from which the Balaur draw their power, just as Daeva use Aether. This has resulted in a weakness of the Balaur... Aether is literally poisonous to them.

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The power source used on the Steel Rake is called the Drana Generator Chamber. In another place we are told that the power source of the Steel Rake is of Balaur manufacture.