From what I gather you're entire theme of the contest with the rules limits many branches of creativity, in a situation like mine I do not actually use the projectiles directly in the spell, I only use it on the ranged units that are setup in the demo. This means that even with the projectiles library in the demo map it is not directly used within the spell in any way, other than enumerating them (as units would be enumerated). I'm out of this stupid contest though, you clearly have a poor understanding of script functionality if you're going to disallow knock-back and group it in the same category as the caster system. I guarantee people will be using xe in one way or another anyways, which defeats the entire purpose because xe is a follow-up to the caster system.