The stats don’t look impressive, but what really counts is the traits and spell effects. Looks like the boss has 4 or more colours with 32 mana, if the spell is some weird *15 bonus to damage for every purple gem then it’s pretty much a one hit kill at any level regardless of stats. Likewise a trait that adds 10 to all stats on 4 or 5 gem matches would also be silly difficult if handled wrong.
Still as someone in bracket 70 in gw I’m very happy for a new reward system that doesn’t require me to spend months playing to get a slightly better pittance reward