I propose this page for deletion :D
The Numbers axis of Naughtymancy used to be an entirely different school called "Deletionism" WoT 8/19/09 until the Titans realized that Retconjuration would be necessary for them to properly maintain Erfworld, and retroactively replaced Deletionism with Retconjuration. As a removed school of magic, this kind of makes Deletionism an example of itself (As a ret-con'd school of magic, Retconjuration is also an example of itself).
- As of yet Unknown.
As of yet, no known historical Deletionists have been introduced.
Deletionism might have been used to destroy weak (non-notable) units en masse.
Maybe Disbanding was originally considered Natural Deletionism, with Rulers erasing non-notable Units (those dubbed unworthy of their Upkeep). A Deletionist Caster would have the power to Disband enemy Units.
Possibly Deletionism lives on as a specific application of Retconjuration, wherein things are retroactively deleted from history.
Real World References
Deletionism is the school of thought amongst Wikipedia moderators that argues for immediate deletion of articles that don't meet the notability standards. Rob Balder is an outspoken critic of this practice.