Some random ideas I would like to suggest -
Barren Battey -
Neglects/halves spell effects of any spell.
Reverse Tile
If an attacker's troop land on this, they start to defend for the defender against the attacker. This will prevent swarming to some extent. Reversed troops die as soon as battle is over
Disorientation Tile
Troops which stand on this get disoriented for about 15-30 seconds
