Add Gun/Rocket Assault Craft

The Western allies developed several specialized, heavily armed landing craft for close support of amphibious landings, which you can represent as "ground"-class units that have sea movement:

• LCG(L)=4.7inch naval guns, 119mm is close to JagdTiger's size (tank class)
• LCF2 FlaK=20mm (AD class for air-defense of ground units)
• LCT(R)=Rockets (artillery class for support fire of ground units)