So it's possible to skip bosses 2-6 in the boss rush, you can actually skip freddy too but it softlocks the game, so don't do that. The trick is to line yourself up on the right pixel and then jsut walk backwards a little. One warning is that if you move 1 pixel too far, you have a chance to spawn extra boss fights, so practice first!. Here are pictures of all of the proper pixels.

¤Note by Rayquaza911¤ I found it helpful to look at the rocks on the far right of the screens, make sure you do not their shadows, that will let you know if you're gone to far. Only the first skip requires 1 pixel more to skip.

Head Boss Skip

Right above the player's head are some rings, this is done on the 4th one in.

Hand Boss Skip

Bat Boss Skip

Ghost Boss Skip

Head and Hand Boss Skip

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