I have replied in length on YT, here I can add some very obvious I think advice to what the others said:
- Molotovs cause Cyberdisc to burn, damaging them slowly but surely, and are relatively safe to use.
- Laser weapons can be picked up from fallen enemies. They out-tech anything you have by 2-3 classes. Even pistols are sometimes better than almost all your guns.
- Smoke grenades can be used to help with the Flamethrower approach.
- Hammer works, but you have to get the enemy isolated and out of Reactions, so this is a very risky venture. You'd also need several hits.
And less obvious (but you know vanilla Cyberdiscs):
EDIT:
And last but not least... You're NOT a champion. You start as a challenger. Becoming a champion is the goal, not your birthright. But don't take me too harshly. I know you're a warrior and you won't back out of a good challenge! I'm trying it to be hard but fair.