Deus Ex: Human Revolution - Interview @ Eurogamer
Eurogamer: How does stealth (cloaking) work, exactly? I assume it doesn't last forever, or does it?
Jean-Francois Dugas: It uses energy. We have what we call "passive" and "active" augmentations. All "active" augmentations use energy. When depleted, you can't use it any more. So, you need to find/buy nutrients to recharge your energy cells to use your augmentations again.
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