
move 1: Trick Room
move 2: Endeavor
move 3: Confuse Ray
move 4: Toxic
item: Focus Sash
nature:
ability: Magic Guard
LvL: 1

move 1: Trick Room
move 2: Surf
move 3: Psyshock
move 4: Fire Blast
item: Leftovers
nature: Quiet
ability: Regenerator
evs: 252 HP / 4 Def / 252 SpA
I don't know how you want this to play out, but this is how I'd deal with it with my Rarely-RarelyUsed team.
Solosis gets up a free Trick Room, and the only way it won't take down one of Kabutops/Moltres with it is if Moltres Roosts when endeavor is used, and in that case a toxic can be thrown (if roost-stalling out TR is the plan), before another endeavor finishes it off.
Under Trick Room, Slowking has no problems killing either of the two 'mons one-on-one with Surf.
--------------
Is this the right way of approaching this? This "core" won't win against the two above in absolutely every scenario, but I assume you're talking about a two-on-two match, so you don't have to factor in having to switch in on them. If you do, then you can probably disregard my entry.