execution- sf4
reaction- bb
The one I spent the most time playing. 
a3, gg, st
they all helped everything, but probably gg the most, those frc’s took some time to learn
^ I cry for u too
The Street Fighter II games with Turbo settings. Those games are so fast, and some of the stuff is whickedly hard to combo. Not to mention that it’s an all-round brutal game where you can lose in under 10 seconds. Most other games are a cake-walk in comparison.
Soul Calibur 4 & super turbo for reaction, and super turbo also for execution.
Marvel, 3s and FRC shiz I guess~
marvel for execution reaction and zoning…all have lead to mii being able to SA3 through a wiffed low forward…
KOF 98 helped my execution loads what with all the difficult links, short hops, and general zoning nightmares, after that I’d say Guilty Gear-- learning to do super cancels in third strike helped me with my awful (it’s still awful) stick execution oddly enough. Keep practice!!!
Guilty Gear by far. Marvel hasn’t done that much for me because I play Team Z and their execution doesn’t seem too hard in general.
Vampire Savior, CVS2, and ST. By the way, more people should play CVS2 and Vampire Savior. 
“I’m a beast, but how do you do shoryuken on a stick, man?”
For execution, definitely Street Fighter III: 3rd Strike, the King of Fighters XII (any KOF game really), Battle Fantasia and Garou: Mark of the Wolves. You’re required to cancel basic attacks into supers in those games with the exception of 3rd Strike which allows you to cancel basics and special attacks into supers.
Street Fighter III: 3rd Strike really helps with reaction too.
Playing games like Marvel vs. Capcom 2, the Guilty Gear series and BlazBlue just helps you play more offensively in my opinion. The links and execution in those games are a piece of cake.
Super Turbo
in that game your fundamentals have to be solid before you can even actually PLAY the real game
you’ll just get throw looped to death by random scrubs otherwise
Initial basic stuff SF2:WW where I did my first ever special. Beyond that a variety of games.
For 3d fighters Tekken 2 and then later on VF4:Evo to help me go up a level. VF4:Evo had the best learning tools of any fighter I’ve played. They really helped not just your execution and reactions but your strategy too.
Watching a top Japanese VF3 player destroy 100 players on TV 12 years ago really made me think about how to apply wakeups. He perfected the final player with wakeup pressure mixups.
3s for me. I feel like I actually haven to slow my timing down to play SF4.
Marvel is alien fast.
I am one of those kids who’s learning FG’s from SFIV/Blazblue. I didn’t get involved in the scene or learn games in depth until BB was released, but since it’s all but dead locally I picked up SFIV for competition.
They’re really good games for beginners. Playing El Fuerte has taught me a lot about the importance of risk vs. reward, mind games, and punishing on reaction instead of over-relying on prediction and getting raped. Most BB characters are insanely easy, but my main is Carl who has by far the most difficult learning curve since he requires a lot of negative edging for basic combos, positional awareness, and perfect execution since against most characters if you mess up his infinite once or twice you’re screwed. It’s also helped remove my scrub tendencies - every time I’ve lost in a BB tournament it’s been to a Tager player, despite the match-up being 8-2 in my favor, because I feel bad and like I don’t deserve the win. But I’m learning to show no mercy at tournaments at truly play to win.
Also MvC2 is too pro for me, I’ve tried to learn it and that shit gives me migraines :bluu:
VS is mahvel junior. The main reason I play the game is to understand rush down concepts better and apply them to marvel.
Playing Marvel for many years = reaction time. 3s for meaty’s, links, blockstrings and buffering/ JoJo’s for those strict links the game has.
CvS2 taught me execution. Roll-Cancelling, and all the possible special and super move motions.
*Best memory of 3s was when I first got it, I tried to combo Ibuki’s Reverse DP + K (into her SA1. Taught me special cancelling pretty quickly.
**C.Viper’s EX Seismo xx S.j -> Flame Kick helped with execution too.
Tekken 3 and UMK3 helped my execution/reaction abilities
KI - Taught me how to evolve from the d-pad to joystick, as well as piano/gatling combos.
SFA2/3 - How to combo into supers, how to DP properly.
MVC2 - Execution, execution, execution.
GGXX - How to FRC within 3 frames.
CVS2 - How hit stun can link to anything.