You can play an extra card, but -5 hand size. (Allowing 6 of a kind!) Would be super fun to mess around with. Idk what other restrictions it would need to be balanced
#Legendary Joker Idea
mellow iron
It would have to be incompatible with blueprint/brainstorm, and unlocking it could require full completion
south sinew
nah 6 card hands would be too weird
also for this to work you'd need 11 handsize at minimum
obtuse glacier
If it's a Legendary it's fine for it to be unbound, but the issue is what would you even do with 6 cards? It requires a complete remake of the game to make 6 cards hands which is kind of pointless for a single joker that you have only a miniscule chance of finding.
And if you don't, it's basically just playing 5 cards plus an extra one for a surrogate discard.
mellow iron
If it requires a full rewrite then yeah maybe it’s too much work
obtuse glacier
It might make for a mod, and I'm sure it even exists.