You don't know who gaul has in his posse he could have chuck Norris, hulk hogan, stone cold Steve Austin and Usain Bolt

while it is true that he commands the entire legion, most were either taken or killed by oryx or us (the local forces at least) in the first game. Gual only managed to win against the guardians by supprise attack on the tower (which he wouldn't have been able to do to oryx) and we were away from the tower at the time (if players had been there at the time he would have had a much harder time). it will only be a matter of time until a bigger threat appears and Gual is nothing but a side character in a bigger story.

We're yet to see what the light does to him in the later parts of the story, imagine Gaul with Sentinel Titan abilities!!!

To be fair, the only reason we stand a chance against anything is because of the Light. It was the main reason Oryx could not Take us. Gaul surprised attacked (how?) us and cut us off from our power - leaving us without our Light.

Who would really win, Crota or Skolas?

Ghaul = Batman Oryx = Darkseid Sure, Oryx was a literal god and had a huge army at his command, but we had the Light on our side and the Traveler too ( during the Kings Fall Raid the Aura of Immortality comes from the Traveler I'd like to think). We beat Oryx in a war of attrition. Lord-wise, the reason we won is because we can basically just ignore death. Ghaul though, he took his time. He studied us. He researched the ghosts and knew about the Light. What's the FIRST thing he does during his invasion? Capture the Traveler. He literally cripples us. If it weren't for the many warriors that DIDNT have the Light, we probably would have been wiped out right then and there. Ghaul also has superior battle sense. We've already seen that those under his command are tactically advanced-the shield brothers were prepared to kill Oryx (and everything else in the Sol system) by detonating the dreadnaught core. We also know that the Cabal have a weapon capable of destroying planets and moons (and suns too I guess). TL;DR Oryx was Superman but Ghaul is Batman wearing a power suit made of kryptonite.

You're comparing apples to oranges here. Yes, full might of Oryx vs the full might of Gaul is a hilariously mismatched fight in favor of Oryx. Oryx is the biggest bad that we're likely to see from a 'mortal' enemy until someone else claims the mantle of Taken King. That doesn't mean Gaul isn't a massive threat to us, and how they act varies. Oryx only showed up because the death of Crota was such a massive dent in his tithe he couldn't ignore it. He had to compensate to keep his Worm fed so he didn't just bum rush the City like Gaul. We also had step by step instructions on how to use the same powers keeping Oryx strong and capitalize on his weaknesses thanks to Toland. Gaul on the other hand had no limitations and no instruction guide on how to beat him. He hit first and he hit hard, scattering the only source of organized resistance immediately. Does he have space magic yet? No, but we're so small by comparison it doesn't matter that we do, he has overwhelming firepower. If you know anything about Warhammer 40K, think of it like this. The City are like the Tau. We're pretty advanced, we got some cool stuff, but we're ultimately an insignificant blip compared to other powers in the universe at large. Oryx was like a Tyranid splinter fleet. Sure the Tyranids at whole are one of the most dangerous things out there, but we only beat a small group of them but we still feel like hit shit for it. Gaul and the Cabal are like the Imperium. Are the Tyranids at large more powerful? Probably, but we're so small in comparison to both it doesn't matter, the Imperium still crushes us like bugs if they care to take the time to do so.

Oryx was weakened after we killed crota and couldn't use his primary power, the ability to take, against us other than to summon hordes of enemies. Ghauls strength is that we are almost nothing without the light. We should have died after he drained out light.

Why are you comparing an ancient region in Western Europe approximating present-day France, Belgium, north Italy and adjacent areas to Oryx?

Ghaul = 800 pound, highly militarized space turtle. Oryx = space demon god thingy that has wiped out countless civilizations himself. Ghaul captured a giant float ball that is in the middle of the longest coma ever. Oryx wins hands (claws?) down.

Gary, Gill? Glenn... Ghaul! Ghaul is a bullet sponge tactical genius who rose to power through hate and has commited planetary genocide (Space Rihno Hitler?). He also has advanced tech, planet and Sun destroying weapons, missile barrages capable of destroying titan bubbles, cabal drop pods that are as deadly as a warsat, a lot of machinery and commands an undefeated legion. Fun fact, even though we are undisciplined for cowering behind walls his Phalynx's have extendo walls that I guess aren't cowardly to Ghaul? Oryx is an insecure giant tranny undead bat who can't even win a war with his own species so he has to take other species including his own to have complete control over them and took himself when we first defeated him because -blam!- it. Before the Awoken fukced up his entire fleet and we -blam!-ed up his super weapon and Oryx himself he had a large legion of hive and taken hive at his disposal who could respawn with throne world clutches, his fleet of tombships and mini dreadnaughts (calling them that), a super weapon which can destroy ships and punch a hole in an asteroid belt and a prisoner in his own ship that nearly took him out. You decide who wins in a fight.