This may sound unbalanced at first but Ars Magica 2 adds a way to pick up spawners. The arcane compendium states that "The ritual removes the spawning capabilities of the spawner, so they will need to be re-added to it somehow." but unfortunately the mod creator did not add the way to re-add spawning capabilities yet so I thought one could take the /challenges mechanic to remove items from your inventory and giving you others and add a use for the inert spawner. Let me list some examples: 1 Inert Spawner + 1-64 Chicken Spawn Eggs = 1 Chicken Mob Spawner; This would limit the number of different mob spawner because only some spawn eggs can be created. 1 Inert Spawner + 64 Feathers = 1 Chicken Mob Spawner; This would allow more variety but the mob drops can be easily aquired if you have a mob farm. 1 Inert Spawner + 1 Crystal Phylactery 100% filled with Chicken = 1 Chicken Mob Spawner; This would allow more variety too. The Crystal Phylactery is an item added by Ars Magica that captures "life essence" of killed mobs. Each killed mob fills the crystal phylactery between 0.1% and 3%. I would say this is the hardest way because you need to kill the mobs personally.