Crystal Maiden is a very underrated character. She can destroy any early game hero especially with this build. A good character to have on your team is Bloodseeker, incase people are jungling. Use you frostbite and basic attack. If you have another person with a stun in the lane it makes it easier to get kills early game. Once she gets her ult any semi-squishy person will be destroyed. To initiate use frostbite run close to them use ult. Again stuns on your team would be really effective. As they try to run away (if not already dead) use crystal nova on them to confirm the kill. After the a few early game kills you should be close to getting Sceptre after that get the following items to keep you alive while using your ult. This is a simple way to carry as CM and it is just as easily turned around with the wrong moves.