I don't know which one is more effective because I haven't used them yet, but I heard that they are good support skills against Terask II. So what would you suggest and why?
Thanks in advance

I like shockwave because it is useful on all the game. But against teras 2 it can provide you a second (even third) attack before he attack you.
i like shock wave, more useful throughout the game
Okay, thanks for the advice
EDIT:
Finally beat Insane.

Prize was the Sword of Apocalypse though...
Your InSaNe! difficulty best time: 265 days, 1 hour, 47 minutes, 55 seconds.
Lol that was a long time... 
Since the question has been answered, I guess this can be locked now.
oh, it's definitely ranged attack. he puts up resistances to magic. ranged attack is not a magic attack, so it gets through every time.