The moment Megara was KO’d, that means that Rex was exposed to very high damage, and I’m guessing the only reason he was still alive was because of his Megara connect, so it makes sense to me.
Ok,…that screenshot has me like:
Meg literally protects the ally from death if they have 1 Hp left!
when she died (which judging from your heroes prolly happened very fast) Rex ied to cuz…He had 1 HP left…
Also remember that Yax’s Body Odor inflicts damage over time over 10 seconds. Assuming everything else worked right, that is what killed off Rex.
Meg and rex had a link like Alexander to his horse R.I.P Alexander!