Prolonged Siege
Soldier
Attack: 2N
Wall: +2N
Where N = Number of consecutive Soldier cards played.
BB code
Effect
Attack: 2N
Wall: +2N
Where N = Number of consecutive Soldier cards played.
Note
i.e. If the last 4 cards you played were Soldier cards, N = 4
Not certain this is implementable, let me know if not.