Originally Posted by
Captain Morgan
As a reminder, this is an invasion,, not a death march. Freiza's MO is to send his goons to wipe all sentient life on a planet and then sell it to the highest bidder. Destroying Planet Vegeta was the exception, not the norm. That makes this more complicated than people give it credit for. For one thing, every Viltrulmite and several other key players can fly at interstellar speeds under their own power. The vast majority of the Dragonball army can't. Only a handful can, and only if you pluck their most powerful versions from continuity in a way that doesn't jive with the OP. Freiza only learned it in super IIRC and this feels like a Z based snap shot. Cell only learned it after his Cell Jrs were destroyed, so that doesn't quite jive either. And I think the only other person is Cooler. All three are way more powerful than anything in the Invincible verse, but they can't be everywhere at once and Viltrulmites shouldn't have major ki signatures to lock onto from interstellar distances.
So after taking initial losses (inevitably ceding Earth or whatever planet makes first contact) the Viltrulmites can scatter to the stars and begin a long, drawn out guerilla warfare campaign. Intercepting and destroying troop transport ships mid-transit or targeting the customers Frieza sells planets to. Viltrulmites live for centuries and can breed with anything even remotely humanoid, so if this is after the empire got over their blood line purity thing they will be almost impossible to eradicate across the universe. They've also shown the willingness to kamikaze en masse, and their light speed charges have imparted planet sundering forces. (The collision would have killed them were it not for a certain unstoppable energy ray, but again, kamikaze.)
The Alliance also secretly designed biological weapons capable of wiping out Viltrum. They should be able to do a new virus here, but I'm not sure if it will work on Freiza and his family. Even Super Saiyans are vulnerable to disease, but Frieza survived things that would kill a Super Saiyan, like having his body torn apart and floating in the vacuum of space for an extended period, which suggests he's not as beholden to normal biology.
And then there's Space Racer. I'm sure many decent Z fighter could aim doge his gun, but I don't think most would bother when faced by a generic alien with miniscule power levels firing a generic looking laster gun. But that Ray gun fires bolts that blast through planets, stars, and everything forever as they fly across the universe at the speed of light. They should punch through even the top Z fighters. So then there's a question of whether the home team can keep Space Racer a secret Kong enough to lure Freiza into an ambush.
This all assumes an end of series Invincible Universe, by the way. If we are talking mid-series, like wherever the TV show is, it goes very differently. Frieza just conscripts the Viltrulmites into his army. Their interstellar flight alone makes them a worth while addition, but there's also a possibility of stacking ki on top of their enhanced physiology or breeding them with other powerful aliens to make specialized super soldiers.
Edit: oh, and I'll note Allen the Alien has a survival feats similar to Frieza but gets a huge upgrade after being critically wounded like a Saiyan.