Well, I suggest starting by giving the original unit and any unit it can morph into (I suppose that would be rock, paper or scissors) the skill Ghost (the one Shade has). As for the changing of units, this can be done in various ways. You could make three skills based on different morphing skills (I suggest Bear Form (Druid of the claw), Storm Crow Form (Druid of the talon) and Stone Form (Gargoyle)) and change them so that the units the skills morphs into is the three units you want. Then add these skills to the original unit and place one unit of this type for each player. Then make a trigger which sets a timer to expire in 15 seconds, and let the players cast one of the morphing skills in order to choose which of the rock, paper or scissors it will play. When the timer expires, remove the Ghost ability from both units via triggers and run a trigger which has a bunch of If/Then/Else-actions (one for each possible outcome of the game). Make the first one check "If Player 1 has Rock and player 2 has Rock", then display Draw (I guess). Make the second one check "If player 1 has Rock and player 2 has Scissors", then display Victory for Player 1. Make the third one check "If Player 1 has Rock and player 2 has Paper", then display Victory for player 2. Then just keep making those for each possible outcome of the game, and then you should have it.
You got all that or do you want something explained more detailed?
