Gafgarion's an odd one. He's theoretically below average at endgame, but is fast during his entire duration as both a temp and a boss. I give him that extra speed credit, but I don't let him use equips past his leaving time. Does get the standard FFT guest/boss immunities.
Gafgarion vs Kazin (SF2): Gaff heals just under a third of his HP against Kazin's low Def, and 3HKOs him. Does Kazin 2HKO that? Nope.
Gafgarion vs October (CSTW): Pretty much the same as above. Gaff's immune to instant death in-game.
Gafgarion vs Gadwin (G1): Not much respect for either's damage, so draining goes a long way towards tilting this.
Gafgarion vs Ashton (SO2): Apparently he has the damage for this.
Gafgarion vs Henry (FE13): Gaff doubles and... only has a 5HKO. Meanwhile Henry 2HKOs. Draining slows this some but with counters offsetting the doubles and the def reducing the healing this isn't a winning proposition for Gaf. No Aegis Shield hype naturally.
Gafgarion vs Tai Ho (Suikos): Tai Ho has good stats and low offence. Not how you want to beat Gafgarion.
Gafgarion vs Jane (ACF): Kneejerk respect for Jane is very low. I guess she has mystic but that doesn't help much here I'd think.
Gafgarion vs Baigan (FF4): Most of Baigan's worth comes from magic spoiling.
Gafgarion vs Garcia (FE8): Kinda like Henry, Garcia is doubled but has counters which largely offset. Gaff has a 5HKO again, so can Garcia kill before then with Hand Axe x3, Silver Axe? Seeing as the Hand Axes barely offset the healing... no, probably not. That's before any evade/WTA concerns.
Gafgarion vs Funguy (CC): Sure whatever.
Gafgarion vs Cinnamon (MMXCM): Below average damage without offensive tricks doesn't work against Gafgarion.
Yun vs Kazin (SF2): Faster and 2HKOs.
Yun vs October (CSTW): Death.
Yun vs Gadwin (G1): Yun is faster, but kills in 5 turns. Gadwin shouldn't have any problem 4HKOing though.
Yun vs Ashton (SO2): 2HKOs, isn't 2HKOed.
Yun vs Henry (FE13): Yun has a 4HKO, and either isn't doubling or receiving counters. Does go first. Does Henry kill in three hits? He would easily, but Yun nulls dark. ... which also drops him to below average speed, so the question is really does Henry kill in four hits? ... oh wait he kills in three anyway. That Thoron is pretty mean.
Yun vs Tai Ho (Suikos): Close. Tai Ho just misses a 3HKO, though, while Yun should manage his.
Yun vs Jane (ACF): Burp, copying Snow. Yun resources are a thing.
Yun vs Baigan (FF4)
Yun vs Garcia (FE8): Again similar to Henry: Garcia kills in three turns, while Yun needs four, and anything which doubles triggers counters.
Yun vs Funguy (CC): Whatever.
Yun vs Cinnamon (MMXCM): Fire resistance.
Meru vs Kazin (SF2): Kazin misses the 2HKO, see Random. Blaze 4 is only 60% to average, LoD weakness is only 1.5, Meru is near average mdur. Anyway she 2HKOs first very easily.
Meru vs October (CSTW): Nope.
Meru vs Gadwin (G1): DKS does 83% to Meru, physicals do 63% (25% to dragoon). Meru juuust misses a 3-2 (127% vs. 85% speed). So... hmm. She attacks, gets hit by DKS, dragoons and heals, takes a hit, uses two attack spells, takes a hit, heals and detransforms, takes a hit, attacks then transforms and heals, takes a hit, uses an attack spells, takes a hit, uses an attack spell and then a dragoon attack (she is now dead). This does... 167% to average, Gadwin doesn't have that much HP.
Meru vs Ashton (SO2): OHKOs.
Meru vs Henry (FE13): Henry 2HKOs with Waste and counters.
Meru vs Tai Ho (Suikos): Tai Ho is pretty solidly killed by Freezing Ring + BSD, and doesn't 2HKO through dragoon.
Meru vs Jane (ACF): I think?
Meru vs Baigan (FF4): See Tai Ho? Again Baigan misses the 2HKO with the second being against dragoon, and he also dies to Freezing Ring + BSD. Reflect doesn't catch summons in FF4, so that's out. And Snow: if -I- don't see Baigan as durable enough for this, no way you should. dat Tellah damage.
Meru vs Garcia (FE8): Garcia only counters with a Hand Axe to me, but it's enough.
Meru vs Funguy (CC): Funguy manages about 93% with a full combo out of the gate! Unfortunately he needs a OHKO.
Meru vs Cinnamon (MMXCM): Cinnamon can probably run Meru out of resources. Neither is really great at killing the other. I suppose Meru could go for a paralysis weapon, except she can't stay untransformed for long since Hyper Cinnamon 2HKOs untransformed Meru.
Gafgarion 9-2. Does anyone really think he's Light?
Meru 6-5. Weird dueller, hates fighters and counters. Still manages to be somewhat underrated? Those who don't OHKO her or counter her give her a mean game to work with, if one of limited resources and ice reliance.
Yun 4-7. Pretty mediocre. The slugging isn't awful: in particular he looks really good against the somewhat fragile, so he can do serious damage in Light. But there are a lot of ways to slow him down.