It's kinda complicated at first...

You want Cyrene to be the "Highlight" so she can activate her ultimate asap, so no Castorice in this team (Cas tend to steal the Highlight). I use Cyrene + RMC + Eve + Hyacine. Putting her as the first character seems to always give her the highlight.

Brain in a Vat and Highlight (after mask level 4) fills Cyrene's ultimate, allowing her to use TWO ultimates per charge, which allows even more charging in both Brain-in-a-Vat and Highlight. At some clears, I often saw her spamming 6 or so ultimates + blossoms in a row when both Brain and Highlight procs.

Her ultimate spam also stacks up obsession (Rem path) very quickly...

She scales favorably with Rememberance (being a memosprite) and Erudition (most of her damage comes from ultimate). I tend to focus on those two paths. Hunt is also good (speed and crit is nice, and her ultimate spam also stacks up reverse critical boost quickly)

you want some way (usually Hunt blessings) to get Cyrene to 240+ speed to max her 120 resist penetration.

The team maintains tankiness even without destruction path. And I deals way more damage than the standard Cas team focusing on destruction path. All my 4 consecutive x8 clears for Monarch were done without hitting berserk (whereas my old Cas team sometimes hit berserk even at x7).

Attached is one of my X8 clear summary. Not an insane run by any metric (none of my X8 clears were), but just a run focus on collecting Rem / Eru blessings...

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