Vendilion Clique has long been one of the best Commanders for one on one Commander. At least I imagine it is. I don't keep up on that stuff, but the card is great, so always being able to cast it is probably great, and that principle holds true in Tiny Leaders.

You don't get a lot of options as a mono-blue player restricted by color identity. Dismember would be a fantastic inclusion, but alas, we're limited to counters, bounce spells, draw spells, and a couple choice permanents. This is the list that I like for tiny Vendilion Clique.

I'm not going to pretend like I got clever here. Clique pretty much forces you to do things a certain way. The worst thing you could do with this deck is not play Vedalken Shackles, with Threads of Disloyalty and Isochron Scepter being two other powerful ways to get ahead.

I like maxing out on answers to opposing Commanders, running the full suite of Declaration of Naught, Spell Crumple, and Hinder. This will give you the best chance of successfully stabilizing and locking your opponent out with counterspells. The tuck rule may have been removed in EDH, but it's still a part of Tiny Leaders.

Vendilion Clique is definitely an expensive card even with the Modern Masters reprints, but now is probably the time to buy if you're looking to own one. The prices have dipped slightly recently, and over the course of this week as the copies from the worldwide GPs enter the market will likely mark the cheapest the card will be for a couple years.