Exactly as the title states. I click the power, the damage immunity lockout triggers, and it seems as if nothing happens. I can verify this for certain in the last 5 seconds of the ability, as I can still collide with objects during this portion (which I should not be able to do) and do not receive the other listed bonuses.
I was considering swapping this in for the leech, which I obviously should not do if it isn't WAI.
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EDIT: And I see someone else a few threads down also noticed this. I apologize for the repeated information if it has been seen by a dev already.