Crystal Maiden is a great support hero that works well against a lot of different lineup combinations. I like placing her in the safe lane (Top for Dire, bottom for Radiant.) but she works in the offlane as well if you're careful. She is REALLY squishy and has a bad attack animation and base movement, but her abilities synergize well with many other heroes. (Juggernaut / Bloodseeker are good examples.) I tailored her build for most situations, but sometimes a change here or there is needed. Enjoy!