Quote Originally Posted by Soukyuu View Post
If their only reason for spell interruption is PvP, then they should just have 2 separate mechanics fro PvP and PvE. Ragnarok online had this to a certain degree (enfeebles and enhancements were nerfed in PvP), why not keep it? If player moves while casting in a PvP scenario, interrupt the spell, else proceed as usual.
FFXI handled PvP different as well, as example with higher resistance to sleep.
edit: they can just adjust magic defense in PvP mode for balancing.