Spawn_Of_Kyuss said:
Arnie's already beaten joey crabface once, and he wasn't even made of unobtanium.
Arnold beat the Predator but then so did Danny Glover. And Danny Glover made a legitimate kill rather than rely on trickery.
I generally assume that, given that a Terminator is designed entirely to kill a given target that it would be trivial to assume that the terminator in question would be well suited to combat both a predator and an alien.
Furthermore, assuming they were both unarmed, the predator is made of weak fleshy easily marred by small caliber bullets which the Terminator has been shown to be able to easily defeat with it's bare hands. Armed or unarmed, the Predator seems screwed.
The alien is in a similar boat. The terminator is almost certainly able to deliver effective attacks against an Alien both with and without weapons while the alien would find it difficult to do the same. While it's claws and whatnot are terribly effective against flesh, I think they would have more trouble with an armored combat chassis. If the Terminator was armed, the alien would be doomed. If unarmed, well then the question becomes just how much blood was spilled on the terminator as said blood has been demonstrated to be effective against various materials including metals of various sorts.