Sega collage!

Starting from top left:

Goliath- Gargoyles

Green Ranger

Sonic the Hedgehog

Sub-Zero

Axel- Streets of Rage Gilius

Thunderhead- Golden Axe

Ryu- Street Fighter

Turner- Comix Zone

Earl- Toejam and Earl

Jimmy- Double Dragons

Megaman

Pulseman

Mighty Max

Earthworm Jim

Rash- Battletoads

Bomberman

Leonardo- TMNT

Strider Hiryu

Vectorman