There isn't an issue of time until you get to the final plate...
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×and that's a false issue (as hinted above). He can't get to the closing plate as long as it's held down, and you can get eyes to do that. Remember also that you can stand on doors... so it doesn't matter if you let him close the door then.
As for the plate for the third chamber...
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×I didn't even clear out all the eyes from the second room before moving to the next plate... I just rushed through to the plate and then picked off eyes from both sides by luring them into there. Then I took out the brains and moved on.
[Last edited by bwross at 07-10-2012 09:22 PM]