The optimal any% route involves defeating Ridley first by taking the Norfair shortcut, then defeating Kraid to open Tourian, defeating Mother Brain, finishing the suitless section and then defeating Mecha Ridley. The optimal amount of ammo for this route gets 50 missiles, 6 super missiles, and 1 Etank, but there are a lot of extra safeties that can be grabbed along the way.
There are 2 important route divergences:
- Right before entering Ridley you can opt to get Hi Jump early or wait or get Hi Jump after leaving Ridley
- After entering Kraid you can opt to kill the Acid Worm to skip having to do a difficult trick, or skip the Acid Worm entirely
The early game is all about quick platforming. There are some strats to make the Charge Worm fight faster, but for new runners the best advice is just to kill it without triggering the spikes and keep going.
The old strats for any% used to skip Charge Beam after killing the worm because you can leave the room while the worm is still exploding. Recently we've found more charge beam strats that at least make the route more consistent with charge beam so you don't have to rely on drops or enemy movement as much.
The Hive Room is also a troublesome room because of how randomly the bugs can behave. The most optimal strat of dboosting into the hives to stay on top of the room is not considered RTA viable because it has such a low chance of success, so the most common strat you will see is to run underneath the hives and lure the bugs after you, then loop back around to destroy the hives before the bugs come back.
The first entry into Norfair is just to get to Crateria to get Power Grip. The reason for getting Power Grip now is because there is an indestructible vine that blocks the path into Norfair to the right, and that vine only disappears after getting Power Grip, so this becomes a required item in order to proceed.
This section shows off the Infinite Bomb Jump after grabbing Power Grip.
At this point in the run you need to be mindful of your ammo going through Norfair. If you plan on not healing, you will want to have at about 18+ missiles when you reach the Ice Beam, otherwise if you're short on ammo it is usually faster to take the refill at the Ice Beam statue. If you plan on getting Hi Jump early then you have a little more leniency with ammo, and also the future option of refilling at the Hi Jump statue if you still need to.
The route divergence of getting Hi Jump early or late is mostly up to your personal preference. The main deciding factors are the cocoon fight and your movement in the upcoming Ridley section. Without Hi Jump, the optimal cocoon fight involves a series of fast wall jumps to destroy the left side in time for the ripper to be in place to stand on it and destroy the right side. With Hi Jump, the optimal fight involves standing on very specific locations and timing jumps/shots to fire two missiles per jump into the cocoon. There isn't any single individual strat in Ridley that saves any significant amount of time, but just about every room has some subtle quicker movement with Hi Jump, and all of those subtle improvements combined with the optimal cocoon fight make grabbing it early end up being close to the same time as grabbing it late.
The quickest path to Ridley is the shortcut in the ceiling to the right of the elevator room which requires one missile followed by a normal shot. If you don't yet have Hi Jump, the quickest way into the ceiling is to bomb jump immediately after breaking the blocks, or a easier strat if you struggle with the bomb jumps is to lure the respawning pipe enemies up to a good enough height that you can freeze one and use it to jump into the ceiling. If you already grabbed Hi Jump early, you can stand on the ledge by the door and just jump right into the ceiling.
The sidehopper room is a very reaction based room because of how randomly they can jump around. Typically you can expect the first and maybe the 2nd sidehoppers to be in the same place every time because they don't have time to jump yet, but the 2nd half of the room is played based on your decisions to freeze them, missile them, or tank the hits and try to survive running through them.
The safest way to handle the pillar room is to wait for one of the blue orbs to drop near the bottom of the pillar and freeze him there. You can jump onto it as a safe platform and climb over the pillar from there. If you're confident in your wall jumps, you can hold a fully charged charge beam and jump into the orb to pseudo screw it and wall jump up to the missile. Also if you grabbed Hi Jump early, you have the option to attempt a very tight jump at the very edge of the platform, which lets you jump fully over the pillar without touching it if you can pull it off.
The next sidehopper room is done optimally by firing two missiles into the first sidehopper and jumping into the rest to dboost through them. There is some luck involved, because you can get a bad boost that pushes you too far back, or they can jump too far in the wrong direction, and both of these situations may cause you to take a 2nd hit. A safer strat if you have low hp and extra missiles to spare is to crouch, fire four missiles, morph and chase the missiles so they kill the first two sidehoppers. Once the third one is on screen, unmorph and fire two more missiles, then remorph and continue through the room.
You will want to refill at the Unknown Item statue to have max hp and missiles before fighting Ridley. If you're sticking with the 1 Etank, you can opt to attempt the Refill Glitch to save a little bit of time. If you're grabbing the safety Etank behind the statue, it's faster to grab that tank before refilling because picking up the Etank automatically fills you up to maximum hp, which means the refill on the way back doesn't spend any time watching your hp increment up to full. Even with a successful refill glitch, it's almost always faster to grab the Etank first unless you already have close to full hp and you get the glitch on the first attempt.
The Ridley (Boss) fight has its own dedicated page.
Ideally you want Ridley to drop Super Missiles so you have 4 supers when leaving the area. If he only drops 1 or even 0 supers, you can opt to farm the owls in the room with the hidden Etank, and the room with the ceiling shortcut.
The path out of Norfair is pretty straight forward. This is the time where you'll grab Hi Jump if you opted to skip it before Ridley.
Nothing too interesting on the way back to Kraid.
Newer runners are encouraged to kill the Acid Worm when learning the run because it's the more consistent path. The Acid Worm Skip (AWS) saves about 90 seconds if you get it first try, and failing it means you either have to reset the entire room or attempt the Horizontal Bomb Jump which is an even more difficult backup strat. Another perk to killing the Acid Worm is you will pick up an extra Etank and 1 or 2 extra missile packs along the way.
If you were able to leave Ridley with 4 supers and you also pulled off the AWS, you may find yourself in a situation where you can skip the refill at the Unknown Item statue. You only need one missile to open the door to the Kraid fight, and 3 Super Missiles to kill Kraid. After grabbing the Unknown Item you will head into another sidehopper room with 5 sidehoppers. They each take 2 missiles to kill, and the fastest movement is to missile all 5 without stopping. If you have less than 10 missiles entering this room, you can do the math to figure how many you need to freeze before missiling the remaining sidehoppers and still have a missile for the Kraid door. (For example, if you have 5 missiles entering the sidehopper room, you need to freeze the first three and then spend 4 missiles to kill the last two).
Enter the Kraid room with Supers selected, hold left and fire 3 Supers as fast as you can. Don't mash the button because they won't come out faster that way, you need to practice the timing to know exactly how fast you can fire them. If you're confident in your Refill Glitch setup you can save a little time by using the setup on the Speedbooster statue. Otherwise you can skip the refill here and wait to refill at the statue after leaving Kraid.
If you performed the Acid Worm Skip, you will need to take a detour into the long hallway under the Reo Room to charge a shinespark, and use that to spark across the Reo Room. If you killed the Acid Worm, it's faster to just ride the rail in the Reo Room. Make sure to have at least 10 missiles so you can kill the Reos before they knock you into the acid or you'll have to ride the rail again.
There is an optional strat after leaving Kraid to pick up an extra Super Missile expansion before Tourian. This trick is known as Brinstar Super because it's the only super missile in Brinstar. You need to line yourself up at the edge of the statue after leaving Kraid and run into the save room to the right. You have barely enough space to store a shinespark here, you may want to pause buffer the down input if you're not comfortable storing this spark. After storing the spark, you can open the door and spark up the save station slope to recharge the spark in the climb room, and hold your charge beam while doing this. In the climb room, wall jump up the left side and if you're holding the charge beam you should pseudo screw the zoomer if it's in your way. Recharge the spark again on the slope you end up on, morph, and ballspark to the left to grab the Brinstar Super. This trick costs roughly 20 extra seconds with all the extra door transitions and item fanfare, and it doesn't necessarily save a measurable amount of time in the upcoming Tourian section but it makes it slightly more consistent.
Tourian is very heavily based on RNG and has its own section dedicated to its details. For Any%, the best advice starting out is to focus on not getting grabbed and staying at full hp as your top priority. If you take any damage, you get more health drops from the metroids and this can really ruin your ammo situation, and the timeloss will snowball out of control once that starts to happen. Try to use supers when you're full on supers, and use regular missiles when you have 0 or 2 supers. The goal is to finish killing the metroids while still being as close to max hp/ammo as possible in order to minimize the time spent refilling on the green rinkas before the motherbrain room.
Zeb Skip comes into play here, but is not a recommended strat for newer runners. The recommended strat is to destroy the first two zebitites, go back into the green rink room and refill to max ammo, then go back into the motherbrain room to destroy the last two zebs and motherbrain herself. More details on this fight can be found in the Mother Brain page.