14% xPb

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Super Metroid Category
14% xPb
14% xPb
WORLD RECORD
2:44:40
1:48 IGT
Full Category
World Record Holder
World Record Holder:
bobbob
WORLD RECORD RECORDING

Category Details

Timing
Start Timer:
On Start Game
Stop Timer:
Entering Ship Animation
Location
Begin At:
Ceres Station
End At:
End of Zebes Escape
Collection
Percentage:
14%
Bosses
Major Bosses:
All
Mini-Bosses:
Boss Order:
KRDP
Glitches
No
No


14% xPb is one of the in-bounds 14% categories that have a known RTA completion. A total of 14 items are picked up during the entire run and focuses on using the X-Ray Scope and Power Bombs for level progression, along with Charge Beam to defeat bosses.

Previous runs of the category used L+R Walljumping to breach the water pre-colosseum. This is not required: A spark may be generated in Crab Shaft using R-mode which can be converted to a blue suit and carried through the Botwoon hallways to spark up this room instead.

Prerequisites

To finish this run, you need to know how to:

Collected Items

Morphball.png Bombs.png Charge.png Xray.png Varia.png Etank.png Reserver.png Reserver.png Missiles.png Missiles.png Supermissiles.png Supermissiles.png Powerbomb.png Powerbomb.png

R-mode CF suit in Etecoons Hallway

Generating an R-mode CF suit with only a maximum of 10 power bombs requires a fairly precise setup. For purposes of this category, this method is currently the most consistent RTA method:

Note this method requires having zero Energy Tanks, so the Energy Tank for Mother Brain's rainbow beam must be collected after doing this setup and before entering Tourian. This effectively means most of the run must be completed with zero energy tanks.

Due to how health gain during a Crystal Flash works, and how it relates to enemy spawns, this method does not always work the same way. There are eight different ways enemy spawn and the CF tick can be related.

On NTSC, the following are the probabilities of this method working:

  • 37.5%: Chance of getting the suit on the first bug hit;
  • 25%: Chance of getting the suit on the second bug hit;
  • 25%: Chance of getting the suit on the third bug hit;
  • 12.5%: The suit may be gotten if a bug hits you within the first two CF ticks.

Since there is barely enough time to be hit by three bugs, the last two cases require more precise setups. However, with a nice, simple setup, two bug hits is quite feasible. Thus, this is effectively a 62.5% chance. A more precise setup could increase the odds; this has not been looked into yet, since 62.5% is fairly good.

On PAL, the bug will normally only be able to damage Samus for four frames which is not enough to trigger Reserves. The method can still work, if the bug damages Samus as early as possible. This results in a 50% chance of working, and requires a 4-6 frame window.

This can be improved: Normally, two CF ticks are needed for energy to enter Reserves. However, if a CF is initiated with exactly 50 energy, then only one CF tick is needed. This makes it always work, but the frame windows don't quite line up. Based off one test, the following are the probabilities if the CF is initiated with 50 energy:

  • 333-334 frames between enemy death and power bomb placement: 37.5%;
  • 335 frames: 50%;
  • 336 frames: 62.5%;
  • 337 frames: 87.5%;
  • 338 frames: 75%;
  • 339 frames: 25%;
  • 340 frames: 12.5%.

Thus, one can see that the setup is inherently inconsistent on PAL. Even if you place the power bomb frame perfectly, it will still only work 87.5% of the time at most.

TODO: Do a similar check for frame windows on NTSC; 62.5% of the time, they will be huge, but may as well check.

L+R Walljumping

To avoid L+R walljumping, a spark must be generated to get up Halfie Climb Room.

Past Mt. Everest, this method can be used to generate a spark.

This method has a tight window, and also is dependent upon crab RNG.

TODO: Look at frame windows here, against the different CF tick options.