Tremor Shells

When selecting a target for a THUNDERFIRE CANNON model from your army. Until the end of the phase, each time that model makes a ranged attack, subtract 1 from that attack's wound roll, and, if a hit is scored against a target that is not TITANIC and cannot FLY, then until the start of your next Movement phase, halve the Move characteristic of models in the target unit and subtract 2 from Advance rolls and charge rolls made for that unit.