I want a whole damn platoon behind me! Make it like Overlord!

Yes and no.

How I would do it, is actually make a unique item, like a channeling plinth where you place the Undead Raiser on, and it spawns 1 skelebro every like 90 seconds, up to the limit for the item (2 at lvl 2, 4 at lvl 4?) but also a large area mob limit (Like Lox) so you can't have too many.

Any time skelebro is spawned, the object loses some % of its durability, eventually breaking.

Like Pike Fences, when you destroy (Either through build or from it just dying due to summoning too many) you are NOT refunded the cost of the dead raiser.