Celtic Heroes

Shatter is way better than sweeping for 2 reasons:
1) shatter lowers the armour of your opponent which makes you able to hit harder with both skills and auto.
2) sweeping blow is , like u mentioned yourself, very slow and only usefull if 2 or more mobs attack you at the same time.

So my suggestion:
Max shatter to 25/25 and cast it before u cast your other dmg skills + dont cast stance or any other non dmg skill while your opponent is still shattered.

Enjoy!

Shatter
Even so, you should still use sweeping blow at 1. Mirrors your auto damage, and it's good when mobs gangbang you.

I would suggest shatter. You can use sweeping blow at level 1 because it hits the same as your auto, and is helpful when many mobs hit you at once. While attacking only 1 mob however, shatter is very helpful, and often when I used shatter before giant swing, my damage on that giant swing is 50% higher. Good luck with whatever you choose .

Max shatter

Both. For lvling, sweeping blow is very useful than you think, because attracts the targets, and high dmge can get you to lock it more often. Shatter is very useful for higher dmge with other skills and in general, so both combinations would be powerful.

Both. For lvling, sweeping blow is very useful than you think, because attracts the targets, and high dmge can get you to lock it more often. Shatter is very useful for higher dmge with other skills and in general, so both combinations would be powerful.

each skill point in sweeping blow adds 10 dmg in averege, now decide if to max it