The End is Nigh

• You have all your movement abilities from the start, but the game doesn’t tell you how to use some of them until later.

• The first keys to open the locked blocks are in the world where Flight of the Bumblebee plays, you can’t find any before then.

• Every screen has a tumor unless the tumor marker is crossed off.

• Sometimes a tumor is easier to reach if you come back in from the exit, but occasionally backtracking is impossible without restarting the whole area, so it’s usually worth trying to get it “the right way” at least a couple times.

• You should try to collect a decent number of tumors even if you don’t plan to 100% the game.

• If you see a little gap in a wall, etc that seems like a pain in the ass to get to, there’s probably a small secret there.

• The second ending and the final area are unlocked by finding at least
  450
  tumors. Then, when you meet your doom, instead of fleeing,
  jump into it headfirst
  .