Invincible Iron Man #13

Eros died in Guardians Of the Galaxy (2019) #6 but due to being a full Eternal like his brother Thanos he was automatically resurrected by the Eternal's Great Machine. However they kept him imprisoned in the Exclusion until the AXE: Judgement Day event when he became useful and even temporarily Prime Eternal. This is his 1st app since that event.

Gameworld may well be the Casino Cosmico that was owned by the Elder Of The Universe Grandmaster in Silver Surfer (2016) #7 but was taken over by his fellow Elder Profiteer for Empyre: Fantastic Four #0 and FF (2018) #37. But it also appeared as Gameworld in some other places such as X-Men (2021) #1-3 & 11-12 where it was run by Cordyceps Jones.

Forge is the X-Men's inventive genius but his mutant power makes him achieve his results intuitively without necessarily being able to explain how he did it.

Makluans are a dragon-like alien species whose most famous member is Fin Fang Foom. The Mandarin found his Rings in a Makluan spaceship that had crashed on Earth. The warrior souls embedded in the rings eventually influenced him to try to resurrect them in Titanomechs that he created during the Future arc in Iron Man (2011) #521-527. Mandarin died in #526 and the sentient Rings began independent existences until they came into the possession of the Source Control black marketeers in Iron Man (2020) #20-25, where they ended up in the hands of Ironheart who has learned to do even more with them.