Which 5-star to Rank 5?

BarkingPineapple

FYI, I have a 4 to 5 mystic rank up gem.

Unassignedtester

Colossus (R4 Sig 50)

I’ve never played colossus before, but I have heard great things about his damage and immunities.
Mojo needs high sig to be anything amazing. Hulkbuster is good now, but I don’t think a champion worth r5.
Magik is great for power control, so if you need a power control champ go with her, but I think most people will recommend colossus.
In the future Id recommend you listing what content your focused on for better advice on rank ups.

10or_Strong

Colossus (R4 Sig 50)

Colossus is the best of the bunch; he's one of the best in the game, IMO. I also am personally quite fond of Hulkbuster after his buff. Magik can never be a considered a bad choice if you need power control.

But truly, you will NOT regret having a R5 Colossus. I use mine in so many different aspects of the game.

Thicco_Mode

Magik (R4 Sig 20)

I think magik's power control is invaluable. if you need power control, def her. if you don't, then colossus

Hendross

Colossus (R4 Sig 50)

Colossus, but since Magik isn't' available as a 6star, I can be convinced.

SpideyFunko

Colossus (R4 Sig 50)

use the gem on Magik, catalysts on Colossus.

Ezra7676

I guess colossus. I'm gonna r5 mine for AQ with OR

CaptainGame

Colossus (R4 Sig 50)

I recently took my colossus to r5 after my main content clearers were omega red, doom, and Corvus. Now they all take a back seat as colossus does all the work. His immunities to almost everything while dealing massive damage is awesome. Add in the omega synergy and he hits even harder. I can’t recommend him enough.

LOThunder

Colossus (R4 Sig 50)

I vote for collosus, but if you're ally doesn't have an annoying AW boss, then you can throw that fat boy mojo on defence at r5.