You mean Cyrus:
I will agree with you on that, level him up correctly and he can literally solo whole missions on his own as his explosives and high powered shot paired with his infiltration ability to stay hidden and there's literally nothing short of detecting bosses that can stop him. In chaos rising, try to have the FC have the ability to reduce cooldowns so he can make energy abilities free, and have Cyrus be equipped with energy based explosives, and the only thing you ever need to be concerned with him is patience and time.
There's another character from DOW 2 that it's nearly as oped as him too in Tarkus:
Let him level up his stamina to full so he can get invulnerability on his tactical advance, level his energy till at least he can use grenades as energy weapons, and he is quite possibly the most important member in boss fights and the 2nd most oped character next to Cyrus as he will not die while his tactical advance is active and his taunt ability is awesome as he can draw enemies attention towards him, making him oped as heck in boss fights as Taunt -> Tactical Advance = him laughing all the damage boss throws at him while the rest of your squad can take down the boss while he's distracted. He also makes an awesome Orbital Strike and Artillery beacon as he is immune to any damage while his tactical advance is active and taunt will draw enemy squads towards him so have no fear using him as bait.
He actually even outstrips Cyrus in opedness in Retribution as Cyrus was toned down a bit while Tarkus got even more overpowered as he can cause crap loads of damage with any weapon he wields. Give him Shadowscale armor to infiltrate and a plasma cannon and he can solo whole maps on his own.
Speaking of DOW 2, there was a time when these units =
Assault Terminators were the most broken things in the whole game as their super heavy armor got reworked to being strong against anything that isn't power, plasma, and artillery weapons, 5400 HP pool, and their than new lightning claws were melee heavy weapons, and they could level up! Summoning even one squad on the field at any point in the game were considered an insta 'I win button' as you could send your whole army at them and the 'clawminators' will murder them with little difficulty. They did balanced them were they made the Lightning claws power melee and reduced their hp upon upgrades to 4500 HP, and they no longer leveled up.
Now Catachan Devils:
in the vanilla retribution are broken as they're a utility squad that is too good at too many roles. Also their shotguns cause the same damage at all ranges while the comparable scout shotguns suffers a damage penalty the longer the distance the target is, power melee weapons that allowed them to beat the crap out of many melee squads and paired with high explosive shot to knock them back to soften many melee squads up before they engage, along with their damnable ol reliable and smoke grenades to ensure nobody bothers them with ranged fire in melee, they're broken as heck.
Thankfully, the elite mod and others rectified that and more.
I've heard Gaijin Entertainment is infamous for their heavy favoritism towards anything Soviet/Russian stuff. There's even evidence to show for it on sites like ED to showcase that they're blatantly Soviet WW2 fanboys.