Imagine that Ultron give some of his minions to Medusa. A terrific combination of two sentry backed up by Medusa.
Each enemies’ move create randomly new attack, protect or strike tile. Each time one of them is matched, either by you or by them, Medusa will generate more AP or burst heal.
As a bonus, imagine this as a PvE 2 
required mission with atrocious scaling.
Is this possible to overcome such madness ?
Which team (except of Medusa itself) would you use to face such a threat ?
if I see this in DDQ guess who I’m going after
as to team, I’d grit my teeth and use self healers…maybe throw in Carnage or Venom (Eddie Brock) whose Green powers improve based on number of enemy special tiles
I guess I’d just stun her. Not exactly Boss Rush level of difficulty here.
A 2
player would have an easier time with them than a 5
player facing +400 level, 100k health sentries
ms marvel, storm and cap or hawkeye
But mostly marvel for the yellows to just turn tiles into team ups, red can remove defense tiles, black for ae hits, storm green for a board shake up + non match tile removal, blue for the super stun ae damage…figure as long as i aint matching the special tiles away it wont be to bad…cap would probably just be a health tank
I’m in champed 3* land, so 2* essential, Scarlet Witch & Squirrel Girl would probably do the trick…especially if Squirrel Girl was boosted that week/event. Boosted Squirrel Girl pretty much wrecks special tile creators on her own.
Honestly, the AP gain for the AI doesn’t hurt you here: Medusa only has one active power and the Ultron sentries have none. Characters like 5* Widow would get the bonus to her abilities with the AP gain the AI has, although with 5* scaling that probably wouldn’t make the difference it would for a players with a partially covered, soft-capped 5* Widow. For 2* players, OBW would make that team an AP battery since it should generally have 3 of every color you can steal. By the same token, Hood would be good here, too, provided someone with more health tanked some/all of his colors.
2/3rds of the AP generated would be useless: the only color Medusa generates that would be useful to that team is purple. The heal would be annoying, but you could just save up to nuke Medusa (or stun her) then you just have the terribly, terribly designed Sentries.
Doctor Fate, shooting every time a power is used.
Medusa vs. Carnage in loaner node today took a ridiculous amount of time. If Carnage animations weren’t fixed, this would be the best defensive team of all time…based purely on how long the animation time would increase the match time.
Time to fix Medusa animations already!!!
… Wonder when the next Gauntlet is? 
Who would I use against that team? Simple. Peggy. Stun the 2 goons and then punch Medusa. 
Her yellow will ensure the enemies use fewer powers than they normally would. Teen Jean to clear some of the tiles off the board and then 4clops at 3/5/5 to generate red Ap and board shake.
IM40 and Ice Man … or Nova …or Peggy Carter … or Goddess Thor
Third Slot for Star Lord (yay cheap powers) although X23 would be fine for some face tanking while waiting for AP to get a stun off.
Wrong doc, wrong company 
but in this case only 1 power isn’t a passive…
You’re right
Too many Doctors around
For every team there is a counter team. For example She-Hulk to steal those tiles, Bullseye to destroy those tiles (and they can work actually together) and then Luke Cage to prevent damage or The Hood to steal AP from the enemy so that they can’t fire powers that often… So I would go with 
3* 
/ 
Sounds like a job for IM40 plus Starlord plus Iceman or 4thor. Focus on yellow or out the gate, maybe even give it a +2 ap boost. Time it right and you can get recharge twice for cheap with an everyone with me on the board. Then stun and smite/snowman your way to victory.
They’re only partially fixed. Partner Carnage with Strange (either) or Power Man (I think; I haven’t tried this) to see what I mean.
Pulled a pretty well-covered Medusa with 3* Storm and 3* Mags in my first match in her PvP. “No problem”, I said.
It was… not fun. I didn’t keep Storm and Mags from getting their tile spam powers triggered, and every single match generated a heal for them.
It was a borderline winnable match – maybe – but it was clear that it was going to take forever and a day, and I might just get attritioned out before I made any headway. So I bailed out.
If I had it to do over again, I’d bring more burst damage characters, as I think nuking before things get out of hand is the call here.
I feel like Medusa with the symbiote guard dogs would be a worse match. Not immune to many of the suggested teams here, but more annoying.