What benifit do the marines add?

[Ghostware]

What do the marines do, what do they add and when should they be used? Do they add some ability to a stack?

[Ace]

No crossing river and amphibious combat penalty for the division they are in.

[ArmChairGeneral]

The Pontoon has similar effects, reducing river crossing times for the whole stack it is in, allowing the stack to arrive with more cohesion, and making MTSG across rivers more likely. It has a second feature, it also gives a siege bonus.

The Marine also has a second feature, in that it is the toughest infantry element you can purchase, with high Discipline, Cohesion and Firepower.

Both are useful in many areas of the map, including Northern Virginia, where there are lots of rivers you need to attack across. Marines commonly see use in Union coastal fort-busting divisions and other amphibious operations. Pontoons are particularly useful along the Mississippi, Ohio and Tennessee rivers.

[Gray Fox]

One Marine element per Division is enough to give the movement bonus, so I put one in each elite Division. If you move such a Division to a region over a river and then add a pontoon to the Division stack, you can witness that the bonus for both will further reduce the movement penalty.

[Captain_Orso]

Unless something unannounced has changed since CW2's release neither Marines nor sailors change the time necessary to cross a river. They negate the invasion penalty, which is IIRC that the defender first-fires his frontage before the attacker fires and no attacking artillery may fire at all. This is for the first one or two rounds of battle and only if the attacker has < 10% MC in the region.

[Gray Fox]

Absolutely correct. My apologies for misreading the ""50% for opposed river crossing" ability description.

In my own defense, I opened AACW last night and in that game the marines aid in river crossings.