The dash does three jobs
Your dash moves you, dodges an attack, and can strike on contact with the right boon. Treat it as a weapon, not only an escape.
A mistimed dash leaves you where the next attack lands. A well-timed one puts you behind the enemy with your swing already coming.
Spacing beats panic
Crowds kill through surround, not through big hits. Keep moving at the edge of a group so only one foe faces you at a time.
If you get cornered, dash through the nearest enemy rather than into the wall. The dash pierces and resets your angle.
Read the tell
Every heavy attack has a wind-up. Learn the shapes and you can dash through the strike instead of away from it.
That habit alone clears more rooms than any single boon. The escape the first biome page puts it to work.
Next: Boss strategies.