Alien/Human Hybrid.

As he got a good look at his new body in the reflective surface of an inactive computer monitor, John could scarcely believe his eyes.

It appeared his new body was something of an experiment in incorporating alien DNA into the human body.

While still mostly human-shaped, particularly in his head and face, Shepard was taller, and a little bulkier than he had been back in the day. All over his body were the same sort of biological armor plates that krogan like Grunt naturally possessed. They were mottled red, and hard to the touch.

Of course, Shepard was at his most alien between his thighs. A decidedly kroganlike cock hung between them, over a foot in length. Accompanied by four hot, heavy balls, already prepared to produce hybrid cum.

"I could get used to this." Shepard thought, happily feeling his augmented anatomy. He'd been told enough times he had a quad worthy of a krogan warlord. Now it was literally true.

Additionally, every vein in his body was glowing green, the Reaper tech augmentations from the Crucible evident at a glance.

Shepard was jolted from admiring his gifted new body by sounds of combat and chaos from the other side of the door.

After a few brief moments, the fighting abruptly ceased. Someone attempted to access the door and enter the room.

Steeling himself, Shepard prepared to make a charge at whoever was coming through the door.