i will assume your character is like gauro from one punch man or baki, highly skilled fighter with superhuman powers
i think in base form each of my main heroes(the knights) would have a difficult time with him but i don't see him walking away the winner in any, and no chance if any of them go into knight form
each knight has 3 power bases usually 1 elemental power a secondary elemental or other power that is somewhat opposite and a third power they have unlike either of the previous 2
here is shadow fang aka the hellfire knight he is( in base form) 7 ft tall weighs in at 374 lbs thanks to being a chimeran he has heightened senses ,stronger and faster then a human he is a master at tae qwon do and karate, has pyrokinetic, umbrakinetic, and a supercharge ability that allows him to double his power for a short time, shadow fang would hold himself back because he would not want to kill anyone, but will kill if it was nessacary , as for strategy shadow fang here is going to tryend the fight quickly and disable your guy by trying to knock him out or break bones, and i would think shadow fang would win