[quote=@Lugubrious]
There's a point at which there are official executions, and then there's a point at which you're just killing someone supposedly as punishment.  Heck, I'll bet someone somewhere uses taste-testing bleach for quality assurance as a valid execution method.
[/quote]

The execution in Oswald's background was an official, sanctioned execution. The methods would not be acceptable in any of the Four Kingdoms, methinks...