Okay there's two ways you can do it:
1) Play legit - pick a bow to pick them at range or use weapon with riposte for example two handed weapon (block skill is a must!).
2) Use cheats (yes they don't disable achievements)
Hold shift and press: right, left, right, left, up, down, up down for god mode
Hold shift and pressL up, down, up, down, left, right, left, right for 100x damage (because some enemies are annoying).