Unique Matching Weapons

I was looking into a few old RPGs and there is one thing I've noticed that isn't done too terribly much is matching weapons. Not just ones that are cutely named, but ones that have effects that compliment each other. I was thinking of perhaps a primary weapon (Personal preference would be a semi-auto rifle) that has an effect like "Critical shots with this gun cause sister gun _____ to do extra damage for ten seconds" Then the other gun (Thinking maybe an SMG) says something like "Critical shots with this gun extend the effect placed by sister gun ____". Now this could even be used two ways. A player who has both guns (let's call em Fire and Ice for now) could use them, taking shots off with the semi-auto, until they score a crit on a Fallen Captain then scooting in there and unloading with the little SMG. Or, two players, one has Fire, the other has Ice, qand they work using communication to actually sync their effects. Now, these guns would likely have more awesome effects, and they would be hard to get, them on either side of the world, with entirely different types of quest, so forth. ((Now as for the extra effects, I'd love to see the semi auto have something like an unlimited mag. So you don't reload, but simply pull from your maximum ammo. This would work wonders for tactile, precise players. You're more spray and pray players would be better suited with the SMG, which could have something like the fewer bullets left in the clip, the higher the rate of fire. Just something along those lines. )) ((Sorry for the repost, posted in the wrong spot. ))