That was back in secret wars 2. Over 30 years ago in real time and more than a decade in marvel time. It's been a while.
Since then he/it merged with molecule man and evolved into "kosmos" and later into "the maker".
The maker took mortal form for some reason during annihilation, and Thanos lobotomized it because killing it would just mean it would be reborn elsewhere in a more powerful, non mortal form.
The maker got killed anyway when the kiln was attacked to free tenebrous and aegis. We never saw where the "rebirth" of the mature being took place and It hasn't been seen since. unless you count that strange encounter by the illuminati where they tried to imply it was an inhuman, which is clearly being ignored at this point.
Hmm, there's still some thing's that don't make sense yet, i mean i guess the question is.....did they do a partial re-retcon back or a full one? since we know the secret wars beyonder's realm was way more massive than marvel and he was basically that sentient realm, not to mention power wise. One beyonder should have been over million's of time's more powerful (or more) than living tribunal, atleast that powerful when they are within marvel.
Which is why i find it strange there was 3 of them to take down the LT..unless the other 2 were just playing around or something.
At this point i just don't think it's a full re-retcon, atleast in term's of the character himself. I suppose i'll just wait and see.