Martin Reyna is a SHIELD agent whom was in charge of the organization's special S.T.A.K.E. unit. He has the power to change into a werewolf-like creature. How he came into this possition and his background has not yet been revealed.
Martin Reyna was created by AL Ewing and Stefano Caselli and first appeared in S.H.I.E.L.D. Vol.3 issue 9 (2015). He then became one of the stars of the new Howling Commandos series. He should not be mistaken for the other Warwolf (Vic Marcus) character that was part of the previous monster-team.
Major Story Arcs
A new Warwolf
Martin has taken the alias of Warwolf, much like the previous werewolf-like agent Warwolf (Vic Marcus). He has been working Paul Kraye on a number of top-secret projects. When SHIELD agent Dum Dum Dugan was brought back from the dead, he was added to the rooster, much to the dislike of Martin. He and Paul Kraye eventually agreed to try to get rid of Dugan in fear of him discovering their secret projects.