Crystal Maiden

Basic Strategy

 * Crystal Nova is a good AoE nuke that also slows your enemies. You can hit enemies from 1100 units away with it (700 casting range+400 AoE radius).
 * Frostbite is a great disable which prevents target from moving or attacking. It also interrupts chanelling spells and teleports. Unfortunately it does not prevent enemy heroes from casting spells.
 * Arcane Aura should be prioritized as it benefits the whole team greatly especially one with a strong caster/ganker line-up.
 * Freezing Field is an incredibly strong spell. But it's rather random and usually gets interrupted by your enemies very fast. Freezing Field consumes a lot of mana so use it sparingly.
 * Items like Black King Bar and Lothar's Edge are viable options to prevent your opponents from cancelling your ultimate, but CM usually won't have that much gold to spend.
 * CM can either babysit her team's carry on dual/triple lanes or roam between the lanes to gank enemies.
 * Always ward woods. Wards should be bought over and over again to provide map control through the whole game.
 * If you have a few coins to spare - always buy items that boost your survivability, or get yourself an escape mechanism like Blink Dagger or Force Staff.
 * Crystal Maiden has a ridiculous backswing animation after casting her spells. Remember, it takes only 0.3 seconds to cast a spell, always cancel the idle animation after that.