After playing a dozen or so games online and many more versus the training dummy, I noticed that it may be beneficial for some armies to force a "closed" game versus an "open" games and vice versa.

My initial thoughts are captured below, and may change after playing more matches. Also, by stating "prefers", I am not saying that one should always try to force either an "open" or "closed" game. In many cases, it will depend on the opportunities that present themselves during play.

"Classic" army prefers both* - Since this is the original army from chess, there are many books, articles, blogs, etc. on this subject. *Long story short, it all depends on the board setup and the remaining pieces. Therefore, the "Classic" army may favour either a "closed" or "open" game

"Animals" army prefers "closed" - with the tiger's ability to move/pounce in short range, elephants rampage ability with short ranged movement and wild knight's normal ability to jump over pieces and, when needed to, captures its own pieces, I would say that "Animals" would prefer a "closed" game.

"Two Kings" army prefers both* - I would think that the "Two Kings" army would prefer a back-and-forth dynamic of both types of games. "Closed" when a potential whirlwind attack would benefit the "Two Kings" player. However, the very nature of the whirlwind attack may change the game into an "open" game, which could allow for an easy mid-line invasion victory, or open up the "Two Kings" army to a long ranged attack or checkmate. *So, it all depends on the board setup and the remaining pieces.

"Reaper" army prefers "closed" - the opponent playing against a "Reaper" army may be forced into a "closed" game from the start as each piece away from the back rank is in constant threat of the "Reaper". Therefore, the opponent may need to ensure that each piece is defended. The "Reaper" player could use this to their advantage by using their "ghost" to clog up the enemy king's movement and eventually setup checkmate, or use this potential gain in tempo to attempt a mid-line invasion.

"Nemesis" army prefers "closed" - perhaps that I'm still stinging from the back rank mate Southpawhare had setup in a previous game, but I would still suggest that "Nemesis" prefers a "closed" game. Similar to the "Reaper" army's "ghost", the Nemesis can be used to clog up the king's movement in a "closed" game to eventually force checkmate. This is enhanced by the "Nemesis" pawn's ability to focus their movement towards the king. The one downside I see playing a "closed" game with "Nemesis" army is the Nemesis' strength is its also its weakness. The enemy army may be able to ensnare the Nemesis, blocking its movement entirely, since the Nemesis cannot be captured or capture anything besides the enemy king. This would render the Nemesis as useless in this game, forcing the "Nemesis" player use their pawn movements to promote to other Nemesis.

"Empowered" army prefers "open" - The "Empowered" army greatest strength is when the rook, bishop and knight work together to gain eachother's moves. Therefore, to increase the chances of this happening would be in an "open" game, to allow each piece the freedom to move adjacent to one another. When the rook, bishop or both are adjacent to a knight, they would be powerful in a "closed" game (as the rook and bishop would be able to move as a knight). However, this advantage in the "closed" game would be short-lived, once the rook, bishop or both move away from the knight and losing the ability to jump over the enemy pieces.