Synopsis
Legacy (Genis) and his mother Elysius have returned to her home in the moon Titan after years of hiding. He's reviewing the battle with Nitro (in Captain Marvel #34) which exposed his father Captain Marvel (Mar-Vell) to the gas which eventually killed him. It was only recently (Silver Surfer Annual #6) that Genis learned who his father was and was given a copy of his Nega-Bands, thus gaining some of his powers. He has only now learned the details of his death, and was ignorant when he accidentally met Nitro (Secret Defenders #14). Now he swears revenge.
Elysius tries to talk him out of it and convince him that his father wouldn't do this and wouldn't want him to. But the young man is pig-headed. His foster-father Eros tries to sway him with his pleasure-stimulating power but his 'son' is wise to that and flies away from Titan. Eros' father Mentor assures him that it was best to let Legacy go to learn by experience, rather like Eros himself did.
Now we move from the moon of Saturn to a moon of Jupiter where Jack Of Hearts is recovering from the beating Thanos gave him when he and Terrax abducted Ganymede of the Sisterhood. He now sets out to rescue her and make the villains pay. Said villains are on Thanos' spaceship Demeter hoping to get information from the last of the Sisters about their sworn enemy Tyrant - info which can help them when they attack him. When she awakes Ganymede refuses to help them.
Later Genis is recording in an audio-diary as his father did. He says he's travelling by spacecraft because he hasn't yet learned how to navigate space by himself. He's been following Nitro's trail through interstellar low-life and it's brought him to Hala, once throneworld of the Kree Empire but now devastated like the Empire by the Nega-Bomb (powered by CM's own Nega-Bands) (at the end of the Operation Galactic Storm crossover event). He understands that the Kree gave Nitro his exploding power as 1 of their Lunatic Legion (as part of a story that CM#34 is an episode of).
Legacy lands on Hala and confronts the villain, who admits his guilt and that he recognised the youth's resemblance to Mar-Vell when they met earlier. He says he never thought much about his fight with CM (liar, he sought him out for revenge) but was faintly pleased to hear that he'd caused his later death from cancer. Angry Genis rushes in and Nitro explodes at him. Legacy fights back but his foe taunts him that like all 'heroes' he won't kill him. Genis strives to prove him wrong and the fight gets more vicious. The holes they blow in walls eventually lead to a military museum which includes weapons that Nitro utilises. But Legacy wades through everything to beat his enemy to a pulp beneath a memorial to Captain Mar-Vell. As Genis is about to power-punch through Nitro's head he sees a plaque with a quote from his father "Defeat your enemy, do not become your enemy." and he realises that Elysius was right.
So Genis takes Nitro a prisoner back to Titan. Elysius slaps the face of the murderer of her husband before he's thrown into a special cell. Then Mentor says he wants him, Elysius and Eros to meet a visitor. It's JOH who tells them what happened last issue. He's come to Titan for help because Mentor is Thanos' father. Eros offers to go with Jack to free Ganymede. But Genis says *he*'ll do it. Mentor thinks that wise because Thanos knows his brother Eros well enough to defeat him but Legacy is an unknown. So Genis bids farewell again to his mother and he and Jack fly off into space using their own powers.