This Experiment 627 is far more aggressive, stronger and far more superior that his predecessors. He has a much larger set of abilities than 626. In addition to his altered appearance he has an extendable appendage in his mouth similar in a way of the Xenomorph's famed secondary mouth.
List of Abilities
Telekinesis to freeze 626 in mid-air to obtain an experiment pod.
He can generate four extra arms, sharp claws, four spines that come on his back, two antennae on his head and a secondary head.
Virtually 626's set of abilities
This creature's unusual weakness is laughing uncontrollably.