Gohan has a scar on the left side of his face as a result of injuries sustained during a battle with the Androids.
Specifically, in Future Trunks' timeline, Gohan fought valiantly against Androids 17 and 18 to protect Earth. During one of these intense battles, he received a deep wound that left a lasting scar. This same fight also resulted in the loss of his left arm. The scar serves as a permanent reminder of the struggles and sacrifices he endured in that timeline. Even when Future Gohan was revived and his arm restored in Dragon Ball Z: Shin Budokai - Another Road, the scar remained.
