So the way I understand it is you can launch skeletons individually for 1
each and do 5 damage to the opponent player/creature targeted?
It's kinda weak, but I can see 4 of these on-field, launching 1 skeleton each turn for 5 damage each, 20 damage per turn in spell damage. That's pretty tough.
That's a powerful card, yes, but here's what makes it crazy - 'Launching' a creature would activate death effects. 3 Elite Boneyards and a Bonewall shield = 3 Skeletons per 1 launched, so if 4 Bone Mages launch a Skeleton, you'll get 12 Skeletons back as ammunition and +8 Bonewalls to your shield.
I think you should make it a note and a mechanic that this sacrificing doesn't activate death effects. Considering it's also only 5
to begin with, and they practically pay for themselves after the first boneyard/skeleton/soul catcher combo. Then imagine an SoR on one of these with Soul Catcher. Suddenly, you make back half of the quanta you payed in the first place and have more more more ammo, and have done 10 damage to something in one turn.
If that's annoyingly long to read, I bolded the part that's important.