Brock Rumlow (played by Frank Grillo) first hit the MCU as a main villain in Captain America: The Winter Soldier. By the time Civil War rolled around he was far more dangerous that the average Hydra agent. And he had a vendetta against the Avengers, Captain America in particular. Of course by then he wasn't Rumlow anymore, not really. He was Crossbones.

Copying Crossbones' look will require a little bit of DIY. This will mostly involve painting a black X onto the front of a chest protector and adding the skull details to a black hard mask. You will also need to add the ammunition to some should pads to recreate Crossbones' armed-to-the-teeth look.  Under it all you should wear a black compression shirt and utility pants as well as black combat boots. A thigh holster, costume pistol, and utility belt round out the look.

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