The CMOA that always comes to mind when I think of UF in general is Corwin's batshit insane rescue in Daggerdisc at the end of S1.
Others I can think of off the top of my head:
*Like blackaeronaut said, the entirety of The Revolution Will Be Televised should count as an extended CMOA.
*The reveal of the Butcher in Manhunt.
*Wakaba leveling the Black Omega facility with a Dragon Slave in S4.
*The Valiant's counter-boarding operation against Klayvor's ship in S3.
*Gryphon fighting with the Teikokukagekidan again in Aegis Florea 2: Commander Moreau Reprise (more specifically, when they start singing the theme song).
*Gryphon and Sumire's duels in both parts of Aegis Florea.
*Juniper taking on the spawn of Nidhogg solo at the beginning of S5.
*Corwin, Utena and Kozue's recapture of the Valiant in S4.
*Liza Shustal's reintroduction to the cast in S2.
*Knights of the Tenth World, Part 3.
*Corwin's instatement as a god.
*Utena and Anthy's wedding, as officiated by Corwin.
*Utena's speech in S5 to the wedding guests about why there will be no actual wedding.
*Utena and Corwin's "mini" wedding ceremony.
*Corwin's aborted curse on Mike Carpenter.
*Utena blasting Gryphon through the dojo in S1 (which subsequently becomes a CMOF).
...and I think that's it for now. It's sleepy time.
Others I can think of off the top of my head:
*Like blackaeronaut said, the entirety of The Revolution Will Be Televised should count as an extended CMOA.
*The reveal of the Butcher in Manhunt.
*Wakaba leveling the Black Omega facility with a Dragon Slave in S4.
*The Valiant's counter-boarding operation against Klayvor's ship in S3.
*Gryphon fighting with the Teikokukagekidan again in Aegis Florea 2: Commander Moreau Reprise (more specifically, when they start singing the theme song).
*Gryphon and Sumire's duels in both parts of Aegis Florea.
*Juniper taking on the spawn of Nidhogg solo at the beginning of S5.
*Corwin, Utena and Kozue's recapture of the Valiant in S4.
*Liza Shustal's reintroduction to the cast in S2.
*Knights of the Tenth World, Part 3.
*Corwin's instatement as a god.
*Utena and Anthy's wedding, as officiated by Corwin.
*Utena's speech in S5 to the wedding guests about why there will be no actual wedding.
*Utena and Corwin's "mini" wedding ceremony.
*Corwin's aborted curse on Mike Carpenter.
*Utena blasting Gryphon through the dojo in S1 (which subsequently becomes a CMOF).
...and I think that's it for now. It's sleepy time.