Wait, this isn't a Rajang! (SP SPOILERS)

[Moth]

Salunga

vs

Gabara

vs

King Caesar (Showa)

vs

Greather Rathalos

Location:
RULES:
Scaled
Salunga has electricity powers
Gabara has Godman powers (venom, detachable claws, smoke breath)
There is some archtype in the area, it grows throughout the match, with it covering most of the area (think Tokyo in SP) after 10 minutes into the battle.
No retreats.

Verdict:

Honestly this just depends if Rathalos can ward off Salunga enough through melee and his poison claws to where the other two can wail on him to take him down. Salunga is a hardcore bastard though, so it would be a challenge to put him down or if the poison would even effect him. I can see Greater Rathalos taking the win since I doubt Caesar or Gabara would enjoy Salunga's apparent strength and Gabara definitely wouldn't enjoy Rathalos' poison talons. King Caesar could also get the win, as he isn't effected by the poison or electricity most likely (made of stone), but if one things for certain, Gabara is just here to die, even with the additional powers.
Leaning towards Salunga or Rathalos taking the win.

[GodzillavsRayquaza]

Could King Caesar redirect a Rathalos flamethrower or fireball? Would that blow Rathalos up if his own flame got directed back into his mouth?

Anyway, I think this actually comes down to King Caesar or Salunga, as King Caesar is pretty dang strong in melee and he is skilled at fighting, it doesn’t look like it because he’s fighting Showa Mechagodzilla, but I guarantee any other Showa Godzilla kaiju except Godzilla himself (and maybe Hedorah) would have done even worse in a 1v1 with Showa MG. Gabara dies immediately, and Greater Rathalos wouldn’t be able to do much in melee with KC and there’s the fact that KC might hard-counter him like I said earlier.

We don’t know how electricity would affect KC, I would actually assume quite a bit because he has golden gears inside him and is essentially a machine. Combine that with the fact that taking Salunga down with just melee would take forever, giving Salunga plenty of time to wear KC down, and I give this to Salunga.

[Breakdown]

Salunga wins the long game due to basically being unkillable as far as the other contestants are concerned. King Caesar will be the only other one standing, and as infamous as I am for defending KC in FMs, I really can't see him being able to put down Salunga with anything he has. Salunga himself is also pretty strong, so most likely he'll wear down KC through sheer attrition.