Marvel Puzzle Quest
MPQ Tips and Guides
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Newb Report 01: Legendary Token Fail
In my experience 1 5 star doesn't hurt the difficulty much. 2 is maybe too many for a 2-star champ roster, if you can't handle some level 150 missions.
Just Dropped In
I found one 5* was a huge scaling hit for PvE. At the time I pulled the 5* I didn't have any 2*s championed. I basically had to get lucky to get the last 2-3 clears in a PvE event. The opposing team would chew up my other two characters and leave me basically one on three. With only one ability to use.