I had something strange, both heartening and disappointing, happen in a recent game. I attacked an army of Swiss rebels which, as one would expect, contained Swiss pikemen. They were all formed up on the opposite corner of the map at the base of a slope. Funny place to put their army I thought. However then I realised what the AI was thinking. Forward and to the right of the main force, in a forest, was another two units of pikemen facing toward the main force. Evidently the AI was trying to draw me into attacking the main force before springing their surprise attack on me. Problem was, the pikemen were in spear wall formation so I could see them plain as day. A minor issue but one that ought to be dealt with (the AI should know not to put units it wants to hide in spear wall formation).