An interaction on Magic Online brought up some discussion in a thread (
http://www.mtgsalvation.com/forums/magic-fundamentals/magic-rulings/627234-interesting-hallowed-moonlight-and-jace-vryns#c3)A player activated Jace and Jace was exiled and then stayed exiled. The player expected Jace would return as his planeswalker self.
Replacement effects usually only involve the game state prior to an event. The exception being when something is trying to enter the battlefield for which we have 614.12 and its concern about what the permanent would look like on the field.
When looking ahead does the “enters transformed” instruction affect the view?
Some argued that entering transformed is a replacement effect so is taken into consideration similar to a Clone copy effect.
There has been a counter argument that effects like persist, undying and “returns/enters transformed” aren't replacement effects because they aren't replacing anything, rather they are just one shot effects that occur simultaneous with the instruction to have something enter the battlefield.
If the former view is correct, then that replacement effect could be applied first and the look ahead would see a planeswalker entering and Moonlight would no longer apply. This would also indicate that MtGO is bugged with the interaction.
However, if the latter view is correct, the look ahead would see Jace the creature on the field and Moonlight would apply - exile city and MtGO is doing it right.
The Origins Release Notes don't indicate what *should* happen.
Is MtGO handling the interaction correctly or is it a bug?
edit: it was pointed out that the look ahead has to see a flipwalker enter as a planeswalker for it to get loyalty counters irrespective of the Hallowed Moonlight.
Edited Todd Bussey (Aug. 26, 2015 12:49:23 PM)