Underground is a stage in Tekken 4. The fight takes place in a room where many people cheer the fighters on. They are near some boxes, crates, and barrels. A small bit of the floor that is elevated on one side of the stage can barely be stepped on.
- The people cheering you on and the boxes count as walls.
- If a fighter is knocking their opponent into the walls, this can cause a cheering person to fall to the ground.
- When you hit one of the onlookers and KO the opponent, the replay doesn't show the onlooker getting hit.