We use the 30minchallenge tag (it changes to something else automatically, but it still works) for all of the art submitted to us that has to go up on Derpibooru due to Tumblr’s rules :3
The artist is fearingfun though and you can easily find it that way as well.
Don’t worry about ‘bothering’ me by the way, it’s really no trouble at all to answer people’s questions!