10 Missile Zebetite Kill

It is possible to kill all Zebetites except the first using precisely 10 missiles.

Zebetites have exactly 1000 health, and missiles deal 100 damage. Usually, Zebetites gain health for every frame they are on screen. Thus, one would initially expect this is impossible: Even if the Zebetites are manipulated to be on screen for as little as possible, they will still be on screen for some finite amount of time. However, Zebetites do not gain health for 5 frames after damage has been dealt. Thus, if a Zebetite is moved on screen for fewer than 5 frames, its health will never increase.

Therefore, by carefully manipulating the screen position, it is possible to: (1) Fire a missile while the Zebetite is off-screen, (2) move the Zebetite on screen for fewer than five frames while the missile hits; (3) repeat with remaining missiles.

Current best RTA setups

The current best RTA setups on NTSC and PAL are very similar. They involve taking a hit by a Rinka (to avoid the turrets sniping during the setup), performing a quick mid-air morph and unmorph (to be in unmorphed state before hitting the ceiling: You cannot aim down before the ceiling), downbacking onto the Zebetite platform (making sure to downback into the wall to keep the positioning normalized), and then turn-around spin jumping to the left.

The final parts of the setup are different on NTSC and PAL, in order to get to the correct screen position. See the below videos to get the precise steps.

After the setup, the process is again the same: When crouched on the ground facing right, turn left and fire a missile, jump in the air, and turn right in about a 3 frame window. Then jump in the air, turn left, and turn back right on the ground to get back to where you started. Repeat.

Double kill

The above setup only works on the second and fourth Zebetite.

Luckily, the second and third Zebetite can be double killed. This is accomplished by hitting the second Zebetite after it has died, but before it has exploded. What you hit the Zebetite with can be any projectile: In particular, it can be a beamshot.

Thus, while killing the second Zebetite, you should repeat the setup for an eleventh shot of a beamshot. This will then kill both Zebetite 2 and 3.

First Zebetite

The first Zebetite cannot be moved off screen, so cannot be killed in 10 missiles.

First and last shot of the kill

In theory, the first and last shot do not need the full setup.

For the first shot, it doesn't matter if the Zebetite is on screen beforehand. Thus, in theory, one can fire the missile with it on screen, and then quickly move it off screen. With the new setup, this doesn't seem like it would be particularly helpful.

For the last shot, it doesn't matter if the Zebetite is on screen afterwards. Thus, one can fire the shot with it off screen, and then just run to put it on screen as the shot would hit.

Applications

The main use of this kill is that it makes 13% xCharge possible, i.e., this was the last step to solve 13% RTA.

It is also used in a number of 14% categories: Specifically, those categories that avoid L+R Walljumping and do not collect Ice, cannot shinespark, and do not underflow. This leaves 14% xGravity, 14% xBoots, 14% xGrapple, 14% xSpring, 14% GravPb, and 14% Gravboots, currently.

This also simplifies analysis of low% categories, in this and rom hacks that do not significantly modify Mother Brain. Specifically, Mother Brain 1 needs 20 ammo, so 10/10 ammo works. It being possible to defeat the Zebetites with only 10 Missiles means that no special consideration needs to be given to the Zebetites. This means if you are thinking about something like low% RBO or low% map completion, you can ignore the Zebetites.