Just wanted to add my 2 cents on Djinn because she is definitely my #1 fighter.
with 50% piercing, metergain and attack stats from her moves plus a maxed out leech marquee (hooray 35%), she absolutely shreds frost armor nodes on rift.
If the water season didn't have the *gain 5% meter every sec while being in an elemental advantage* modifier, Djinn would be without a doubt the best of my whole roster to beat the bossnodes (even at elemental disadvantage yes).
She pairs perfectly up with Evergreen Evil, which creates a constant buffed Djinn 10 seconds into the match (I've faced an invincible Djinn for 40 seconds straight). With a last stand valentine she can also get right back up to max health after getting hit by e.g. an unblockable blockbuster.
In conclusion: Djinn is worth to invest in.