Cage, Medusa, Fist, or Nova

Calnexin

I've lucked into a predicament where I'm going to have to sacrifice one or more 14th covers.  For whatever reason in the last two weeks the magical unicorns came rolling in and I've got four characters that need Iso.

5 days - Medusa and Nova, 1 each
8 days - Iron Fist, 1
13 days - Luke Cage, 2 covers, one more coming from PvE progression tomorrow.

Needless to say I've stopped opening tokens for the moment.

Cage is the only one not on the chopping block, because 3 covers are better than 1.  I've got almost a full week between him and the rest of the pack.  But I need to make sure I don't deplete my resources to the point where I can't afford to champ him, so one or more of the others have got to go.  Doing my maths I find myself with 470k "surplus" to spend on non-Cage characters prior to his cover expiration - only enough for one character.

Nova - I've been trying to cover him forever.  The surplus cover came because I was sitting on a 6th color from a progression reward when a bonus hero pull completed him.  I'm tempted to champ him because his covers are now rare, but I don't see myself using him long-term since I have a functional OML.

Medusa - Also been aggressively trying to cover her.  I've had to sell 3 covers already, but now she's complete with a cover to spare.  She'll probably see the most mileage, being a top-tier 4*.  But her covers are going to be available in currents for awhile, so one cover shouldn't make a whole lot of difference.

Fist - I happened to pull a 6th color from tokens, then my 3* Fist hit 223 and completed him.  I'm not all that crazy about the character, and he also will be available for some time from currents.  But, since I know I'm champing Cage right after him, there's automatic synergy there.  I don't know how powerful that combo is, but there's got to be a reason they specifically mention each other in their powers.

What would you do?  I'm going to wait until just before expiration to see how much Iso I've got, but I doubt I'll be able to scrounge an additional 200k beyond my initial predictions to champ a second one of them.

abominatrix

Normally, I'd say Medusa as a no-brainer. Nova is very good, but Medusa is... Medusa.

That said, you have a robust 4* roster already, you wanted to champ Nova enough you made him your BH, and more Medusa covers will be coming. I'd just go ahead and do it.

You'll also get more Fist covers, and you'll probably want to champ him eventually because of his synergies with Cage (his special and fortified tiles help Cage's yellow, as does his existence. The two of them together can be difficult even when not boosted).

Ducky

I'd champ Medusa first and Fist second if you could manage it. Since they have a good amount of time left in tokens, they will give you the best ROI.