Invincible and his father Omni-man takes on two Viltrumites. Omni-man is a beast and defeats his opponent Kregg, while Invincible gets his butt handed to him by his opponent. He did his job though in keeping his opponent engaged long enough for Omni-man to finish his fight and help him. That should have been the end of it but Lucan, another Viltrumite, enters the battle and surprises Omni-man from behind.
From – Invincible #29