Spoiler alert, if you just began reading Invincible please don't read this
 
 
 
So I literally just read all the Invincible books up to issue 76 within the past three days (yea I said three days, I'm vacation lol). I've been looking at whats going on with the V-War and it got me to thinking. Out of all the heroes on earth they only picked up one kid who for the most part we've never really seen at all, Mark, and his little brother (who I still feel is completely useless right now even if he hadn't gotten his a-- handed to him so easily), leaving behind what I felt to be countless other more experienced and in some cases more powerful characters. So with that being said and the way issue 76 ended, who if any do you think will still be left standing on earth to help fight by the time Mark and the others get back. Folks like Immortal and Samson have proven to be pretty much useless against Virtrumites(I think Immortal has been killed by almost every one of em including managing to be killed by Mark and Nolan twice each lol). I know Eve and a few others have shown the ability to be able to hurt them but not much.
 
any thoughts

The thing is, the only characters who could really make a difference aren't Kirkman's characters. He can't take Spawn or anyone like that off into space. So, out of Kirkman's Invincible Universe, which characters could stand up to a Viltrumite? I'm gonna go ahead and say no-one. (though incidentally, they didn't just take Mark and Oliver, they also took Tech Jacket. Not to mention their alien allies, like Space Racer, Battle Beast, Thaedas and Allen)
 
Omni-man, at the beginning of the series, completely annihilated the original Guardians of the Globe. They were the most powerful superheroes on the planet and he tore them apart. Mark has also fought the Guardians of the Globe, and it was only a 'difficult' fight because, as he said, he was holding back. Viltrumites are in another league to most of the heroes of Earth. So, let's take a look at the exceptions. 
 
Monster Girl has stated that she is invulnerable in her monster state. We've never seen the limits of this but, equally, we've never seen her get hurt or wounded. So it's possible that she could stand a chance against Viltrumites, but whether she could hurt, let alone kill, one of them, is unknown. So maybe Monster Girl could have helped. Robot could have been of assistance by sending out a lot of Robot drones, but they'd be a distraction more than anything else. Plus, if the Viltrumites found where the actual Rudy was hiding, they'd kill him. Immortal, as you've already pointed out, is completely useless. The Reanimen give Mark a run for his money, but I doubt they'd phase Omni-man or anyone on his level. There's Mr. Lieu or however you spell it, the old guy who has the Dragon spirit form. In issue 1, Nolan could only beat him when he found the old guy and knocked him out. Which brings up the same problem as with Robot. Eve's powers are a little glitchy at the moment, IIRC, so she may not be a great help, though if she really let loose with her powers she could potentially hold them back single-handed. I'm not sure exactly how strong or invulnerable Brit is, but he could possibly be a help. Maybe Bulletproof, too, if he's durable enough, otherwise he'll just pull an Immortal. And maybe that Giant kid, he could hold his own, maybe.
 
So basically, if we're looking at the Kirkman characters... Some of the Capes Inc might be able to lend a hand, but they probably won't do much. The Reanimen might be able to wear them down, as would Robot. Monster Girl, Mr. Lieu, Brit and Giant might be able to hold their own (though they could just be tossed into space) and Immortal should find a nice underground cave to hide in.

Let's not forget about Meteor Master. Sure, he left in the Invincible #38, stating that the Earth civilisation is "insignificant", but he can change his mind.

" Let's not forget about Meteor Master. Sure, he left in the Invincible #38, stating that the Earth civilisation is "insignificant", but he can change his mind. "