I've said this in a couple of threads that ask this same question. So there are a ton of ways to deal with this kind of player and challenge them without just killing the rest of the party.
First remember that if this player really is a combat beast then his opponents are quickly going to start focusing him and if they've fought him before or are expecting him are likely to come prepared with some bigger guns just to deal with him.
That aside the ways they can deal with the player beyond bringing better guns and mods or talents are:
Entangle, if they're trying to down him this is a great way.
Stun damage, typically these characters will have a lower strain threshold than the rest of the party.
Pen, excess from high pen doesn't hurt softer characters as much as tougher ones.
Spending advantages and triumphs to buff enemy rolls, after all more successes means more damage which can be achieved with more boost dice or dice upgrades.
Spending triumph to damage his armor, if it takes enough hits recklessly it's going to start wearing down after all.
The stun effect, causes direct stun damage through soak, enough said
Lastly but far from least is NEVER underestimate how useful minion groups are. Individually these can fight your weaker players as they're less likely to have a big bad soak monster barreling down at them but when they combine remember that they have 1 skill rank per minion in the group after the first, this means a group of 6 has a whopping skill rating of 5 which is nothing to scoff at if they're say skill 4 because then you're looking at a roll of YYYYG that can, and justifiably should, be divided to several far less accurate GGGG when firing at other players (since they're not likely to focus fire players who are not shrugging off shots like a walking tank).
Also remember that if they've been spending their advantages and triumphs on bonuses they may be packing some extra boost dice and upgrades as well. Even with a small weapon at that point they can become scary in large enough numbers.
Edited by Dark Bunny Lord, 22 September 2014 - 03:01 PM.