Door Clips

Normally to transition from one room into the next room you would need to open its door to walk into the transition. There are some doors in Zero Mission where it is advantageous to go through the door without opening it because it would require using ammo that you either don't have or are trying to conserve a specific amount of it. It is possible to use the Ice Beam to freeze and enemy such that Samus is stuck between the enemy and a door, and have the frozen enemy clip Samus through the door without opening it.

These clips are very precise and depend on the subpixels of the enemy approaching Samus, and they only work on doors that exit to the right side of the screen.

The most common door clip you will see is in the first Power Bomb room in the 100% run. This door clip has an RTA viable setup that guarantees a Space Pirate to be in the correct subpixel position every time, and it allows you to conserve one extra Power Bomb in this section and this enables a major route difference to avoid a shinespark chain later in the run.

The setup for this door clip is to jump up to the powerbomb pedestal just high enough that you ledge grab it, and climb up to collect the power bomb. Hold right the entire time so that you walk off onto the smaller pedastal, and let go of right after walking off of that one. While still in the air, tap A so that you spin while in the air, and do not move after landing. This setup makes the Space Pirate walk the perfect distance behind Samus, and once it gets ready to shoot Samus is when you look up and freeze it. If everything was done correctly, just crouch, then hold right and you'll be pushed into the door.