Blizzard Assisted

Recommended before you choose a specialization (while the game reports the Death Knight's initial specialization). Highlights the spell Blizzard's Assisted Combat suggests next, the one rotation advice the game still lets an addon read in Midnight combat; it waits while you cast or channel. Alongside it, the reminders every Death Knight premade shares, each once you know its spell. When you choose a specialization at level 10, that specialization's premades take over.

Adapted from Blizzard API documentation: C_AssistedCombat (12.1.5.70529), Blizzard client data: ChrSpecialization (the class initial specializations, order index 4).

In game: /rm set initial chooses it by hand; it loads only for its edition and class, and is listed only for the specializations it is for.