People have trouble pking attackers or defenders in the tower because of all the slippery ice,so i'll give a few tips.
Attackers:Start out with 1 person running around and killing people,it will be a distraction and almost everyone will run after them.While they are chasing the decoy,send everyone else out to attack the flag,Because not many people will be at the flag,you have a bigger chance of taking the tower.The more people you have,the better.I'll give tips for defense later.
Oh,and send the person who has the best control as the decoy,so they can pk easier and run easier on the ice.