The more Steam Points you expend in the Steam Engine, the further the Steam Tank moves in the Movement phase. Declare how many Steam Points you will expend in the Steam Engine at the start of your Compulsory Moves sub-phase. If you choose not to expend any Steam Points in the Steam Engine, the Steam Tank's Movement will be 0 that turn and it cannot move at all. For each Steam Point you chose to expend, the Steam Tank's Random Movement increases by D6".
If the Steam Tank charges an enemy unit, it will inflict an additional D3 Impact Hits for each Steam Point expended in the Steam Engine that turn.
If the Steam Tank is in base contact with an enemy unit, it cannot move but can instead expend Steam Points in the Steam Engine to grind foes beneath its wheels in the close combat phase. Select one enemy unit in base contact – it immediately suffers D3 Impact Hits for each steam point expended in this way.