What it says in the title. I opened up the Create Homebrew Monster page, intending to create a modification of the Piercer monster. In the drop-down menu under Monster, Piercer is missing (I tried both typing it in and just scrolling down).

It's present for me, do you own the monster manual? It's not a free monster.

I do, and can access Piercer elsewhere (e.g. on the Monsters page), and other non-free monsters show up in the list for me. Not sure why this one is missing for just me (I imagine there may be others missing as well, I just haven't checked systematically).

Are you sure you own it and not just having it shared via campaign content sharing?

Oh yeah, you two are right, that was the issue. I thought I owned it but actually just have it shared from a campaign. And I now can confirm that creatures from other sources that I do actually own do show up in the list. So apparently sharing makes it accessible in a bunch of other places (e.g. the Monsters page) but not this one.

Thanks both for your help!