I remember I and another fourm user made some posts on horny craft, but after checking today they mysteriously disappeared without any notification, did the dev do this or some fourm moderator? I just want to know what happened
Only the author of a post, moderators and staff members can delete a post. Members owning a thread, like some devs with their game thread, don't have this power. Devs and modders have a bit more rights in the case and can edit the thread opening (and in fact their posts) without time restriction, but that's all.
If there's no notification it's generally because the deletion was a side effect of some thread cleaning ; generally because your posts where referencing deleted posts, or part of the side discussion that have been removed. Then depending of the number of secondary posts to clean and the time the moderator have, sometimes it happen that those secondary posts are deleted without notification.
In case of doubt, or when you want to have more information regarding the deletion, you can
open a ticket and ask for some explanations. But you should wait a bit,
Icarus Media already called the cavalry, you'll perhaps have the answer without needing to open a ticket.