I played a lot of Vanar in S-rank after the Great Vet Nerf of 2015, so I decided to share some well known and less well known tips about the class. Hopefully more people will give it a shot! (Not that I like the mirror matchup...)

Hailstone Prison

1. Its well known but worth mentioning that if you use Hailstone Prision while your opponent has six cards in hands, the minon is gone forever. Begone Spellbinder!

2. You can cast Hailstone Prison on your own minons, allowing you to pick up and reuse a Jax Truesight, Razorback or Keeper.

Chromatic Cold

1. Formerly Magmar's Mana Burn, CC is highly useful in the Vetreviun matchup as it not only removes Scion's Third Wish, but it also cleans up the Sabrespine Tiger underneath.

2. CC targets squares, not minons, so it can dispel minions that are usually immune to spells like Mechaz0r.

3. Chromatic Cold can also dispel tile effects, like Shadow Creep and ironically Mana Tiles. Another Mana Burn nerf!

4. You can't silence artifacts, but in a pinch the damage from CC knocks a durability charge off a General's artifacts or can even deal the finishing blow.

Aspect of the Mountain

1. It says on the card, but you can target your opponents minons. Sometimes they're just better placed, or a Black Solus is out of control.

2. The Mountain Elemental can move and attack immediately if you transform a minon that has not yet acted (like a rush minon).

Frosthorn Rhino

1. If you lose infiltrate during an action, you lose all of your secondary actions. You cant attack, then slip over to the other side of the battlefield for a second attack (while you have celerity during the move, you lose it and your attack).

Hearth-Sister

1. While it can switch places with ANY minon, you can choose to skip her Opening Gambit and leave her in her original space.

Those are the main tips that I am aware of. Feel free to mention any I missed in the comments!