Can you actuvate a bunch of haunted platemails in response to the other haunted platemails triggering?
Like if I trigger 1 {Haunted Platemail} then in response activate another, would I have two creatures
Yes.
7/1/2013 It's possible to activate the first activated ability of Haunted Plate Mail in response to activating the first ability of another Haunted Plate Mail and have them both become creatures until end of turn.