After a player has finished casting his spells, his opponent is allowed to dispel any spells that remain in play (unless they were cast in the same Magic phase) if he has any Dispel dice left. Note that he only needs to beat the casting value of the spell in question - be does not have to beat the original casting score. In addition, these spells can be dispelled in the player's own Magic phase using any Power dice not being used to cast spells, as Dispel dice. Follow the same rules as given above. Note that a spell that was originally cast with Irresistible Force can be dispelled as normal in subsequent turns if it remains in play.