Scripts

function play_anims()
	if GetCurrentPlayer() ~= 1 then return end
	Trigger(REGION_ENTER_AND_STOP_TRIGGER, 'region_name', nil)
	PlayObjectAnimation("creature", "animation", ANIMATION_PLAY_METHOD)
	sleep(3)  -- Pauses will likely be needed between animation plays
	PlayObjectAnimation("creature", "animation", ANIMATION_PLAY_METHOD)
	sleep(3)
	PlayObjectAnimation("creature", "animation", ANIMATION_PLAY_METHOD)
	-- ... --
end

Trigger(REGION_ENTER_AND_STOP_TRIGGER, 'region_name', 'play_anims')

To make the script work, you will need a region; when a hero enters it, the animation will be triggered.

Added 1 minute ago

What does the NON_ESSENTIAL command do, and how can it be used?

The animation will only be played if no other animation (other than "idle00") is currently playing on the object.