Rule number one of to keep a swarm Abyssian board under control. If you let them have 5 wraithlings on board at 5 Mana, they could easily just kill you with their pre-existing options (double soulshatter pact for 27 damage if everything is range; soulshatter pact + deathfire crescendo for 25 damage if everything is in range). Furor chakram is not really the problem here.
But like everyone has said, there are so many ways to keep that board under control with AoE. Also, you’d be wise to clear their wraithlings with your minions if you’re not already doing that.
, do appreciate it, though it really depends on your draws, maybe things just aren’t working out for me 