In addition to what I said in my last comment: You can actually just sit in that lever room the entire time, with a portal right out side of it, and wait until the boss shows up there. When he does, teleport over, and if you can use the ice block, then do it. If not, just teleport back and wait until he returns.
I'm just going to add something that maybe not a lot of people have noticed. At the final level, if you put a portal in the room with the lever, and then walk out the door, you can get back into that room through another portal after the door shuts automatically. It could be useful if you want to easily avoid the boss's missile attacks.
This game was terrible, as a sequel. There was a great lack of new ideas in it. If you're going to make a sequel, be creative. Don't just add a few things and call it a new game.
Ok game, controls are simple and easy to use. Definitely challenging. Can anyone tell me: Does hitting a banana for the first time count as destroying an object?
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