Several maps have two Shaman and two different colored holes. Shaman only receive credit for mice entering their own hole. As a result Shaman often fight until one Shaman is killed. Do your mice a favor and brush up on your battle skills so a moron doesn't knock you over the edge and then build an anvil snake instead of a ramp. All of the following techniques could end up murdering large numbers of mice if you aren't careful where you use them.
 Offensive Techniques
Spirit is a favorite technique since it can be placed anywhere on the map and is usually available. However, it will only be effective if the Shaman is near a ledge. Keep in mind that spirit will affect you too, so you might end up just killing both your opponent and yourself, which usually can annoy everyone in the room. To spirit a Shaman off the map or into a hole, it is best to place the spark under and slightly to the side of his or her feet. Ghost spirits are no longer allowed.
The cannonball, if available, is one of the more reliable ways of killing a Shaman. It is best used by tricking the Shaman into jumping, and then using the time it takes for them to fall to summon it and render them helpless to do anything against it.
One infamous technique often used on Waiting Cheese is to summon a box in front of the Shaman and then cannonball them off the map. If executed properly, this attack is almost impossible to avoid.
If the Shaman is particularly skilled he may cannon your own box back at you before you can summon yours. You can avoid this by summoning a short red ghost plank between you and the box. You may also want to attach a long wooden plank rising vertically out of the box, making it impossible to jump over. This is also extremely effective when dealing with rogue mice.
During battle, a Shaman traditionally attempts to block the other Shaman's hole, or in other cases trap the other Shaman so that he is too far away to build. Shamans should be careful they do not trap mice in the blocked off area or block both holes.
This is very simple: drop anvils over the location in question. You can also use a global anchor on a plank and then attach an anvil to it, similar to the box and plank method. Usually this is used in time critical situations since anvils can eventually be pushed with enough mice.
 Box and Plank
Place a large box over the area you wish to block access to, and then anchor a small plank with a red anchor (B) in the center of the box. The plank will prevent the box from being shifted.
However, glitching red anchors may create a opening.
 Plank Stack
Instead of using a box, you can simply layer a bunch of short, global anchored planks over the location in question, which will usually do the job. This is often used by beginning Shamans who are pressed for time.
This method is also impossible to displace with drag balls, however, unlike a box block.
 Ghost Tactics
 Boxcar of Death
A slow, but fun to watch method is to create a box around the other Shaman, attach 2 balls to it and then use runes to push it over the edge. Note that this takes insanely long to make and you should only do this if the Shaman suspects nothing or you have a truce. This can also be used to eliminate stallers or AFK mice. One thing to remember: Never use a cannonball to speed up the process unless it's attached with an anchor.
 Deadly Airship
You should create a locked triangle arround the other shaman, and then place balloons in it. The Shaman should be stuck in the flying triangle, without any way to get out. As the airship flies the Shaman will be eventually killed. This is easier to do with totems (Just be careful to don't stuck yourself at the airship while placing your totem).