The Prism is not a "best" class. It is a modular engine. Master the Fusion timing, and you will out-damage the Blinkblade. Mis-time it, and you will exhaust by room two.
And that, she realized, was the only guide she’d ever need. frosthaven prism guide
is your primary limiter. Always pair a Fusion turn with a bottom action that doesn’t require movement (e.g., Shield self, Heal, Generate element). The Prism is not a "best" class