Crimson axes not spawning in artificial underground crimson biomes

[Ash_Dies_Alone]

i'm trying to complete 100% of the bestiary on my main world which is a corrupt one, but i can't get the entry of crimson axe because they won't spawn in my artificial underground crimson biome, does it have to be extre large or something?

 

[Aurora3500]

It might require your Underground Crimson to be in the Cavern layer for them to spawn. Your depth meter/cell phone can display the depth level you're at. If your Crimson is at the Underground Layer, I'd recommend building a new one at the Cavern layer.

 

[Banmei]

I just got one yesterday in a custom Crimson biome. It's just a tiny pace up from Hell though. In my experience in the crimson, even natural large crimson caverns, these creatures are kind of rare. Try the cavern out and be patient.