This level is basically a type of horde mode: Kill increasingly more difficult waves of enemies until they stop spawning in, then leave. Simple, yet fun...at first at least. It gets a bit repetitive after a bit, but does keep you on your toes for sure, especially once the stronger enemies make their way in!
SECRETS:
Secret #1 -- 3:24
Once this lift becomes available for use about halfway through the level, use it and ride it up to the BFG9000 is, grab it, then open the computer screen "door" to the right of it for an Invulnerability as well as a switch! This is one of two switches needed to be used to access the Secret Level
Secret #2 -- 5:32
Same as before, but on the opposite side of the labs. This alcove has a Plasma Gun and a usable computer screen door that leads to a Megasphere and the second of two switches needed to access the Secret Level
Secret #3 -- 5:40
This area is only accessible once both the aforementioned switches have been thrown. Take this teleport to be whisked off to the Secret Level!
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