You can make a "living dead"

The glitch allows you to create a mob that constantly glows red and tries to die.

To do this:

Summon any mob, such as a Creaking, using the command: /summon minecraft:creaking

Freeze ticks using the command: /tick freeze

Kill the Creaking using the command: /kill @e[type=minecraft:creaking]

Advance time by 1 tick using the command: /tick step

Target the Creaking using the command: /data merge entity [creaker ID] {Health:1}, thereby restoring its health. Important: You must specify the Creaking entity's ID in the entity selector, as using the command /data merge entity @e[type=minecraft:creaking,limit=1] {Health:1} will return an error: "No entity was found."

Unfreeze ticks using the command: /tick unfreeze

Note that the Creaking entity is now constantly glowing red and trying to die. This is indicated by the Creaking entity constantly attempting to lie down and then disappear forever, which, of course, never happens.