How do you get Crown of Nikephoros II Phokas with the console?

effect create_artifact_nikephoros_crown_effect = { OWNER = root } — runs the scripted effect that makes it, for the character you play (debug mode).

What if the owner can't benefit from Crown of Nikephoros II Phokas?

They get Court grandeur baseline +4, Monthly Renown +5% instead.

Court artifact · Pedestal Item

Crown of Nikephoros II Phokas

FamedUnique

Crown of Nikephoros II Phokas is a famed pedestal item artifact in Crusader Kings III: Monthly Martial Lifestyle Experience +15%, Court grandeur baseline +4, Heavy Cavalry Maintenance -10%. Quality 70 and wealth 70; maximum durability 100, and it does not wear out. Made on 963.7.2 for Nikephoros Phokas in Constantinople. At game start it goes to the holder of Byzantine Empire (starts from 1000.1.1). Patch 1.20.0.3, from game/common/scripted_effects/01_exp1_historical_artifacts_creation_effect.txt.

Quick answers (3)

What does Crown of Nikephoros II Phokas do in CK3?: Monthly Martial Lifestyle Experience +15%, Court grandeur baseline +4, Heavy Cavalry Maintenance -10% (patch 1.20.0.3).
How do you get Crown of Nikephoros II Phokas with the console?: effect create_artifact_nikephoros_crown_effect = { OWNER = root } — runs the scripted effect that makes it, for the character you play (debug mode).
What if the owner can't benefit from Crown of Nikephoros II Phokas?: They get Court grandeur baseline +4, Monthly Renown +5% instead.

This is the crown of one of the finest tacticians the Imperial line has ever seen. Failure in wars west of the Empire, but conqueror toward the east.

Effects

For an owner who can't benefit from it

The template gives these instead of the effects above when its “can benefit” check fails:

Who can benefit (can_benefit) (9 lines of game script)

OR = {
	culture = {
		has_cultural_pillar = heritage_byzantine
	}
	is_roman_emperor_trigger = yes
	any_liege_or_above = {
		is_roman_emperor_trigger = yes
	}
}

As written in game/common/artifacts/templates (justinian_template).

Who can equip it (can_equip) (14 lines of game script)

trigger_if = {
	limit = {
		has_ach_dlc_trigger = yes
		coronation_proper_artifact_crown_trigger = yes
		NOT = {
			scope:artifact = {
				category = court
			}
		}
	}
	NOT = {
		has_realm_law = uncrowned
	}
}

As written in game/common/artifacts/templates (justinian_template).

History and who has it

Made on 963.7.2 for Nikephoros Phokas in Constantinople.
Kept with the title Byzantine Empire from 969.12.10.
At game start: the holder of Byzantine Empire (starts from 1000.1.1).

How it is made

The game creates it with the scripted effect create_artifact_nikephoros_crown_effect. In the console (how to open it), this gives it to the character you play:

effect create_artifact_nikephoros_crown_effect = { OWNER = root }

Built from the effect's file; not run in the game by us.

Source: game/common/scripted_effects/01_exp1_historical_artifacts_creation_effect.txt, common/modifiers (nikephoros_crown_modifier), common/artifacts/templates (justinian_template) and the English localisation, Crusader Kings III 1.20.0.3.