Hover over the icons under "Damage" to see list of attacks.
Strategy: Use Pure Dragon for Pure Metal with Hypnosis/Pure Energy. Use Cool Fire with Snow Storm to defeat Wizard. Finally use Wind with Aurora Borealis/Mirror with Rainbow attack to Crystal,or if you don't have Legend,Use Half-Terra Dragons.
Before the Light and War update, this was the last tournament.
You can see what have changed since the Light and War update here Stadium Update 06-08-13