The strategy for this game varies slightly depending on the number of players.
In two player, the first player wants to place the root near the center, then place on the side that gives him the largest area after the null is placed. (This could be left, right, top, or bottom.) The second player has little choice but to play to the corner of a center root. Then the second player should aggressively invade the territory. Both players then fight to secure eyes, preferably where all surrounding pyramids are 3 pointers. Then force your opponent to place in your pockets and have to point at a 3 pointer and you only ever point at the smaller pieces. Whenever a player will point at an opposing piece, the point swing will be the number of pips on both pyramids and you need not consider if you go more negative or they go more positive. In multi-player you must keep track of the swing relative to the bystanders, too.
In multiplayer, each player trys to section off the largest area and fill it with your larger pieces. Whenever you place a small, you will be invaded, so keep your pieces large. Remember that if it's too big, then one piece can shatter it. You need to have your pieces placed so you have the most spots available for you to play at. Dump your smalls when they can't be attacked, if possible, or use them to reduce other players territory.