Sentinels

From the fictional Marvel Universe, Sentinels are technologically advanced, giant robots designed to hunt down mutants, especially the X-Men. They have evolved and have even travelled back in time.

Sentinels have a wide array of abilities; they can fly, shoot various weapons from different parts of their bodies, detect mutants at long range; some of them can even change form and re-assemble after being destroyed. Most dangerous of all, some varients have the ability to learn from the attacks it faces and create defenses against them which hampers the opponents' chances of defeating them.

The most famous sentinels are The Master Mold[?] and Nimrod.