When the phantom came out it was a massive power creep for ffg.
However since its nerf it has a substantial amount of counters.
First and foremost ps bid is the Main phantom killer which basically makes whisper the only real threat to most lists.
Next anything that does damage through shields or ignores most green die. Wampa, blunt, etc.
Fast and agile blockers such as awings help.
Phantoms are a pain with thier 4 atk dice but soontir is harder to kill.