I was just about to say this, but I think that you need to spend relatively little time outdoors in the Sierra Madre if you beeline for the objectives and don't explore, or go after loot. It does 3 damage every 20 seconds IIRC, so it's going to come down to how much health he has going in.

Case in point: Portal.

No Xbox One (or 360) love. 😠

No Xbox One (or 360) love. 😠

Naw, we think you're adorable.

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