The Lalafel in the opening movie does the same move, only thing that could explain this. would be a short term barrier (not in game atm from looks of what we have). Could very well be unimplemented ideas the game may or may not offer later on, kind of like the enhancement for the Flaming arrow (also from the opening movie).

May just be spells/abilities we can look forward to seeing, or just enhanced visuals. There are few more things that stand out then just those two effects though.