A Game of Thrones: The Board Game (Second Edition)

A supporting player must contribute the area's full supporting Combat Strength or none at all, and support is declared (or refused) in turn order for each adjacent combat (only from areas containing a Support Order). (See rulebook pages 17–18.)

No — supporting units can never be chosen as casualties and do not retreat; only units in the embattled area take casualties and perform retreats. (See rulebook pages 18 and 21.)

Defending units must retreat to one empty adjacent area or a single friendly adjacent area (all retreat to the same area) and may never retreat to the area the attackers marched from; if there is no legal retreat area, the units are destroyed. Routed units cannot retreat and sieges engines cannot retreat. (See rulebook page 21.)

No — an army is defined as two or more friendly units in the same area; a single unit is not considered an army and is not subject to supply reconciliation, though routed units and all units still count toward supply when armies are reconciled. (See rulebook page 8.)

Yes — you may muster Ship units directly into a Port you own even if the connected sea area contains enemy ships; however, you may not muster ships into a sea area that contains enemy ships. (See rulebook pages 25 and 9.)

After calling for support and calculating Initial Combat Strength, both attacker and defender secretly choose and then simultaneously reveal a House card; resolve the cards' text abilities immediately unless the card specifies a later timing (e.g., "at the end of the combat"), and resolve timing conflicts by Iron Throne track order. (See rulebook pages 17 and 19.)