Castform Spawner spawns much too far away. Furthermore, "Air_Persistant" means you'll really struggle to catch them. Most of the time they'll spawn too far away from the platform, headed in the direction they'll already be traveling.

Castform should be male if possible, to make the love ball.

Since it flies off, it should spawn more than one.

Spawner has been given a name, changed to Land Spawning, and given a restricted range. Gender has been limited to male, but might change that back with the inclusion of Duskull