Guilty Gear definitely. I’ve only started when SFIV and BB but picked up GG for “fun”. That game is retarded fast and the execution is beyond ridiculous. When not playing I’d watch videos of japanese play and feel like I’ve upped my game a bit.
Tekken 2 & 3 = execution (king and nina links were strict)
3S & MVC2 = reaction & proper punishment (magneto and Yun… )
Old school Hadouken and DP basics from Super Turbo, fast forward to Guilty Gear XX which taught me reaction, and then finally Third Strike where I learned execution and REALLY tightened up the reaction.
Third Strike was the greatest teacher for me.
CVS2 probably. parrying and jding helped my reaction a lot.
pong, im og baby.
st - fundamentals, reversal timing, pianoing ect.
3s - yomi, execution, os throw teching, meter management.
gg - execution, execution, reactions, okizeme.
bb - how to win simply by picking top tier.
sf4 - fundamentals again. option select throw teching again. turtling really hard.
My execution is still terrible.
So I dont know what game helped me with it the most.
Probably SF1 because I still hit the buttons harder to deal more damage.
For reaction, its definitely call of duty 4.
When youre at a high level in that game, if you see a few pixels out of place, within a fraction of a second, you have to sweep across the screen and kill them with pin point accuracy or else die yourself.
Tekken 2, Alpha 3, and MvC2. Then GGXX when I started playing FG’s again a few years back.
Link timing in Tekken is brutal, and marvel is… well, marvel. Guilty Gear is great for reaction time and execution. It takes serious focus to play and win in that game.
Messing around and trying to learn 3rd strike helped with reaction times too, with parries and such. I never real good at 3s though, and it’s something I would like to set aside time for at some point.
World Heroes
hdrrrrr
ST and ST.
Strictly speaking for execution:
ST - precise joystick motions, reversal timing, safe jumping, negative edging, reaction time in general, tick throwing with directional throws
MVC2 - hitting multiple buttons accurately, combo timing, finger endurance, reaction time in blocking
CVS2 - hit confirms, links, kara-ing (roll cancel), pianoing, widest variety of joystick motions (both kof and sf)
GG - air dash mechanics, timing in general (frcs), frame trapping, comboing off random hits, following up knockdowns
3s - option selects, tick throwing with command throws
Most games have a bit of everything but the stuff I listed after each game are the things they teach best imo.
execution = weaponlord(negative edge,strick combos) , UMK3(combos), x-men: cota(dash cancels, cancels, akumas dash/Sj powered specials) Tekken 2(strict lnks) KI(buffering)
Reaction= Xmen:cota(playing as sentinel) Tekken 2(pauls couter move) samsho(playing as galford)
what he said^
:nunchuck:
add TTT-T6 - For spacing , hit confirming , 13f punishing , punishing in general… precise joystick motions
Tekken Tag Tournament. Wanted an update to that game for so long.
execution: guilty gear
reaction, in gaming, in general: beatmania iidx
reaction, fighting games onry: guilty gear
after getting into gear, my game was upped in everything else i was into honestly… i cant say the same about any other fighting games 
My fighting game foundation was built on Street Fighter II: Championship Edition for the Sega Genesis. Although I played fighting games before that, I was never proficient with them until SCE. My skills were further honed by Street Fighter Alpha 2 and NightWarriors: Darkstalkers’ Revenge, both on the Sega Saturn. I don’t think I could ever learn more about fighting games than I did from those three games.
For reaction definitely Marvel. Really it’s the only game where I really am familiar enough with it to always pull up the right answer on a split second decision.
The King of Fighters 98 helped my execution the most.
Melty Blood was probably what helped my reaction the most.
U want a test of execution, go play Guilty Gear XX Accent Core and do a full Testament web combo >.< facking annoying. The infinite web+grave digger is easy for the 1st 3 or 4 times.