Really cool idea to make 2 stars usable

JJBoy19

Before this I used to play a mobile game called injustice (baaaaack in the day) and there was a super cool interaction where the GOLD Darkseid characters super booster bronze characters on the team making them usable when with him. I though this idea can be implemented too but with. Very cool and interesting twist. There are obviously some OP 2* in the pool like magic and quake which is why you can’t have the ability/ synergy of the character to give them states equal the the players rarity but what if it were only to boost there attack to a 7 star rarity (for the 7 star champ that has this ability, 6 star attack for 6, etc) but either only marginally boost their health or not at all thus you can’t even parry that often and it solely relies on skill. What do you guys think? And if yes which character would this ability/synergy be attached too?