A generalized tactic per colour note:
W: Weenie tactics. +1/+1 and -1/-1 and redirection of damage to win combat against odds.
U: Hand disruption, slow down of opponent creatures and Homorid/merfolk midrange creatures. Excellent utility colour with strong blue vs blue bombs as well as Deep spawn and Leviathan.
B: Hand disruption and destroy effects with self sacrifice.
R: agressive and strong midrange while unable to block. Pair with war drums to even out.
G: Defensive walls and elven fortress and slow thallids. Finish with big craw worms or lots of saprolings.