I made myself a Leviathan to level up two dragons in the Kelp Beds, unfortunately it just frustrated me too much (I hate the Kelp Beds). So I'm just using my Workshop Workers to level one dragon at a time in the Golem Workshop, having a chance to get an expensive boss familiar is always nice.
Golem Workshop Drops (Leveling Fodder)
x2x2
Golem Workshop Drops (Leveling Fodder)
x2x2