-He has a scar from a saber across his face that is about two years old
Scars can be a little puffy and they're more glossy than regular skin. They're also discolored. Can be a pink or a brown.
-scraped up knees from falling/tripping etc
The flesh is rubbed off via friction. Reddening of the surrounding area. Swelling. Blood probably would ooze rather than gush. The wound would be very irregular in shape and the texture would be rough.
-a symbol burned deep into the palm of his hand
Same as the scar on his face, just a different shape. Probably more puffy since the burn was deep. Though the symbol would deteriorate over time. The palm of the hand is a bad place for brands and tattoos. Depending on how old it is, it would more than likely be a big discolored patch in the shape of the basic outline of the symbol. Interior detail would probably be lost. Brands should be big and simple. And put on a big patch of skin.
-The scar on his face also leads into one of his eyes.(the initial cut went through his eyelid and into the actual eye but I've got no clue what that would look like.)
He would have lost the eye. Eye patch since the area around the eye was that damaged. Though if it was a long blade, the shape of the eye socket should have protected the eye itself. A saber is a light sword. I don't think it would have had enough force to cut the skull. But you never know.
-and various little nicks (from getting in fights and running around) all over the place
Small cuts can be dark red lines surrounded by pink.
There are tutorials about bruising around here somewhere.
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