Tyr makes his big return in the first of two stories by Paul Levitz in Legion of Super-Heroes 20 (March 1986).
LaRocque and Mahlstedt do the art on the cover story. Element Lad, Shrinking Violet, Chameleon Boy, Ultra Boy and Phantom Girl have been tasked by the Controller to deal with Tyr's death planet, after destroying his Sun-Eater factory. The division of labour is pretty clear. Ultra Boy battles Tyr to keep him busy while the other four study the planet, and try to figure out how to destroy it.
Among the cutaway scenes we see Sun Boy trying to get back with Gigi Cusimano. She mentions Sun Boy's fling with Shrinking Violet, but he tells her that that is not any sort of relationship, just an occasional thing when Violet wants it.
Brainiac 5's hair is getting long, which is a usual sign of him falling into madness again. He has decided that Sensor Girl is really Supergirl, but we see that Sensor Girl is aware of this, and feels badly for him.
Dawnstar does much better tracking the missing Legionnaires this time around, leading Wildfire and Mon-El to Tyr's world.
The five Legionnaires realize that they do not need to destroy the planet, just stop it from being able to move anywhere. Phantom Girl and Violet gut the planet's controls, stranding it in space, just as the others turn up to bring them back. The Controller chooses to stay on Tyr's world to deal with Tyr and his people.
Giffen and DeCarlo provide the art on the back-up story, which features White Witch and Dream Girl. Nura is trying to get her little sister to stop staying in and studying all the time, and pulls a very cute con on her, pretending to get a vision of monsters on the streets.
It's not a terrifying event, though, it's Halloween, and Dream Girl's "vision" was just a ploy to lure White Witch to a costume party. Very nice art, and a charming tale.