How to kill the strogg

ok this has been brothering me, my friends have been saying you cant kill the strogg, if flesh fight them then they will take the flesh when they die and use it, and if machines fight them then they will use their technology. so who or what can kill the strogg, it can be any army, a person or anything, heres a example:

supernoob662 says: maybe the reapers from mass effect can kill them since the reapers have killed so many cillivations

could the dredge from Titan A.E. kill them

Basically any race in Warhammer 40k.sSubZerOo

There you go. Even the Tau could whip them.

the only way they can take the flesh or tech from other races is if they win battles and are able to recover the bodies. if they lose, no loot for them. DDX2

yes but who would lose to them