Multi-Purpose Missiles (TW, p.229) may be used by a unit in a Depth 1 water hex to attack either a target underwater, on the water, airborne, or on the ground. The rules, however, are not clear on what happens when that unit is on land.
1) If a unit with Multi-Purpose LRM ammo is in a ground hex, does it use standard LRM rules (including indirect fire) to make attacks?
2) Under advanced rules for Water Line LoS (TO, p.225), a unit may trace LoS to a submerged unit at Depth 2 or less. May a Multi-Purpose ammo equipped unit, on land, attack a Depth 2 submerged unit?
3) The description for Multi-Purpose ammo (TM, p.261) states that it is just a propulsion system mated to a standard warhead. It even states "... can be used as a torpedo or a normal missile with a standard launcher". This ammo is even listed twice under the weapon and equipment tables. It is mentioned under the Battle Armor table (TM, p.297) and under the standard launcher's Heavy weapon Ammunition table (TM, p.346). May Multi-Purpose munitions be used with standard Clan launchers, such as the LRM-5?
4) TechManual clearly states that Multi-Purpose Missile's propulsion system may be attached to not only LRMs but SRMs too. Every reference states that it may be loaded for SRMs and LRMs. Total Warfare, however, says "Weapon Type: Standard LRMs". May Multi-Purpose Missiles be used in Clan SRM launchers?
