My First Duelist win with 2 challenges

The strategy has been to save all upgrades for the first tier 5 weapon, then use Twin Upgrades and Swift equip to enjoy a variety of weapons.

Somehow I cannot manage "On Diet" challenge with duelist, I might need a lucky start for it.

Elemental Blast is very cool too, I love its crowd control effects like blasting many baddies around with that elastic shield. I forgot to use it on Yog where it would have really shined!