Cassie deals an additional 8% of a target's full hp with Big Game. If Raum has his full soul armor at 8k health, she does about 1320 a weapon shot for 4 seconds. That's 5 weapon shots, which is 6600 damage total, assuming she hits all of her shots.
This one mostly depends on aim. Though Lian has a slight advantage because her weapon is hitscan, so shots travel faster. Though if Lian's misses her presence shot, Cassie wins.
Mal'Damba counters Skye. His gourd can reveal her through his tick damage, he can immune her entire ult and poison damage, and she has no defense to his ult.