Look I'm sorry but that whole meme about Magcargo being insanely deadly because of how hot it is is not accurate. That's bad thermodynamics. The raw absolute temperature of an object only tells a small part of the story of heat transfer, and it doesn't MATTER if Magcargo is as hot as the surface of the sun. Real lava is also rather hot, but you can step in it and be basically fine.

Long story short Magcargo would glow in the dark, but not be blinding, and it would only be mildly uncomfortable to stand too close to one, Magcargo does not scorch everything around it in a 30 mile radius just by existing, trees would not get set ablaze unless they were so close to Magcargo they were practically touching it anyway. The only caveat here is when Magcargo DIES. It's dead body would legitimately be very danger to hang around near, as all that immense heat is now escaping rapidly into the environment, a Magcargo corpse would be very dangerous but at all other time it isn't a big deal.