Legends of Runterra bug during attack and block phase

I could´t blcok when my unit was under frostbite, and another bug ( if its not a mechanic which should be mentioned in game that I did not know of) is when 1 game when a Daruis with overwhelm eff attack my 1/1 unit unit, and I used Glimpse beyond to kill my unit in order to prevent Darius from attack because the attack target which is an actual game mechanic, Darius attack still went threw. Is card with overwhelm do they bypass this mechanic?