Interrupt Practice in Isle of Nameless

well, let's see, difficulty on interrupting:

1/4, 1/2 second: extremely hard
3/4,1 second: really hard (particularly when dealing with Searing Flames, sheez, 1 second cast time and 2 second recharge is utter oblivation, well balance that with 15 energy)
2 seconds: moderate
3 seconds: easy
5+ seconds: you get the drill

Yeah, if you want to interrupt spells in PvE, bring a hero or hench since they have quicker reflexes. For PvP, this is a good idea (since I don't have good reflexes, I often have hard time interrupting spells in PvP with a mesmer)

/signed