The number above the troop name shows the order in which they are queued to garrison. Troops with blue bubbles have shields activated. The yellow icon to the left of the HP bar shows how many shields the troop has active.
is available using the pull out bar on the left side. This shows the unions approaching each gate, their current hp, required travel time, remaining distance, and current speed. Use this to plan attacks.
Encourage the unions on your server once an hour. Encouragement offers an attack bonus to all unions, gives a small reward each time you encourage, and if your server wins War of Supremacy you will be entered to win one of 6 prizes.