Alright, I've been taking a look at this game again in order to (re)gain some useful data that will be helpful in TASing this game. Here's what I've found today:
Here's a list of some of the more notable parts that can be built.
parts: unlock cost effect
hyper dash 2500 1000 invincible dash (no speed bonus)
buster plus +1 400 200 buster damage +1
buster plus +2 1000 200 buster damage +2
ultimate buster 1500 500 always fully charged shot
hyper charge 2000 1000 faster charge shot
armor 2000 2000 gets full x armor (instant effect)
saber plus +1 200 200 saber damage +1
saber plus +2 2000 500 saber damage +2
ultimate saber 1000 800 ground slash always third slash from triple slash
Note that defeating a boss (including the intro boss) yields 200 DNA souls.
Also, these are the memory addresses for the DNA soul count: C0F0-C0F3.
Note that the variables are stored in an odd way: the four addresses stand for the four digits of the DNA soul number. So if your soul count is, say, 2156, then C0F3 is 2, C0F2 is 1, C0F1 is 5 and C0F0 is 6.
Other memory addresses I've found so far are B857 and B85A for boss invincibility countdown. (Former goes at least for Flame Mammoth, the latter at least for Wire Sponge). Boss invincibility after being hit lasts for 60 frames, including being hit with their weakness weapon and being stunned. (Possibly not for all bosses; only tested on Flame Mammoth and Wire Sponge so far)
A semi-relevant fact I'll put down here is that Zero has four weapons which require him to enter the pause screen (which takes at least 40 frames), which makes them very impractical for most uses, and probably aren't worth using at all. (X doesn't really seem to have totally useless weapons). These include Tri-Thunder (Volt Catfish), Lightning (Wire Sponge), Dash (Overdrive Ostrich) and Earth Gaizer (Blast Hornet). The Zero Final upgrade also counts, but it does have notable damage output (10). Probably doesn't make up for the time to obtain it, though. (Capsule sequences take around 900 frames, and that doesn't include the time wasted to reach it)
Some useful notes for route planning (I'll try to design a full route later):
The Saber+ and Buster+ parts are really, really convenient. One can get a Saber+1 part before entering the first maverick stage, and then the air slash will do 4 damage to a boss, which is as much as some weakness weapons on some bosses. But then, after getting 1000 souls, Buster+2 is unlocked, and when X gets both, his buster will do +3 damage, which means his shot (charged or uncharged) does
5 damage per hit, outclassing Zero who doesn't get Saber+2 until way too late.
So first, Zero will be used to pick off some mavericks without very powerful weaknesses against them (e.g. Flame Mammoth, who takes only 4 damage from Fish Fang, or Tunnerl Rhino whose weakness, Earth Gaizer is absolutely useless), get their weapons to beat some other bosses weak to those weapons (options include Wire Sponge, Neon Tiger and Overdrive Ostrich). Then switch to X and pick off the rest. Uncharged weakness weapons with X do 4 damage which is less than Buster+1+2 X-Buster, so the order hardly even matters.
Finally, some useful links:
Damage Data Charts for
X and
Zero
VGMaps: Mega Man Xtreme 2
Gameshark cheats for easy testing.
MMHP: Mega Man Xtreme 2 (general info)
