I’ve noticed that the Monster fights in this game are 50% positioning awareness, 25% good strategy (which hunter to attack) and 25% good aiming and pure skill.
You need to fight when you want and where you want, need to “trick” the trapper to get you a dome in a place that is favorable to you, or that you choose because you attacked them instead of being chased.
If they are hurting you more than you are hurting them, turn around and move to a better position (behind a rock, over a rock, circle the loop, whatever).
So, the average Jack can protect himself with the repulsor, this is not a big deal unless you want to kill him to flee the dome because you are being punished. If that happens, try to endure and deplete his batteries and fire or rock in his face.
Jack can also be in front or diagonal to a good team member and can repulse you from killing him, or good Jacks can only use repulsor when you jump, to stop the jump but not drain batteries… this is way harder to counter, you will need to change direction, to make it look like you are retreating, and then turn around and try to get him by surprise when he changed to pistols.
If this happens, the only way to attack is to avoid damage and jump or move until you can get yourself in position with jack behind you and your hunter of choice in front or side.
For me, the only way to win vs hunters who know what they are doing is to try to avoid damage while searching for an opening, and to do that you need to have the terrain advantage.
You can’t kill medic if sunny drone is shielding and sunny is giving jetpack, and you can’t kill support when medic is healing, even if they are against the wall and you are using all your cooldowns on them, they can overheal and overprotect your damage
But if you have terrain advantage to move around, and you move trying to avoid assault dps and bad positions, and they chase you behind the pillar, and then you surprise by comming back and jump to that hunter and hit him away from sunny drone or medic ray, then is when you can deal damage and kill, or that hunter will try to flee away and not do his job, and then you can change objectives and go for a down.
Griffin can harpoon you and prevent to move away from him, but if you change and move towards the harpoon he is helpless. One hulk smash in his face and he will abandon his idea and jetpack to safety
Jack is opposite, the beam is directional and prevents one direction, so change your direction, change position, climb or move to a better position, and then try to go back to your original objective.
Also, rock throw and fire, only a handful of Jacks would be able to dodge a rock while still pushing you.