Have you ever felt like Planeswalkers would be more awesome if you could use their ultimate as soon as you played it? I have. And now, there is a way.
Before anyone asks, this does, in fact, work within the rules. Behold the comprehensive rules excerpt that proves it:
306.5b A planeswalker is treated as if its text box included, "This permanent enters the battlefield with a number of loyalty counters on it equal to its printed loyalty number." This ability creates a replacement effect (see rule 613.1c).
Thus, as it's a replacement effect that adds the counters, Doubling Season works as another replacement effect to instead put more counters on. I scoured the planeswalkers to find the ones that could end the game basically by themselves with an Ultimate activation and found these:
Chandra Nalaar
Sarkhan Vol
Ajani Goldmane
Nicol Bolas, Planeswalker
Nicol Bolas was out, way too expensive, but the other three work well. Chandra Wraths the board and takes 10 life from them, Sarkhan makes 10 4/4 fliers and Ajani makes two gigantic dudes (remember, Doubling Season!) Together, they provide enough consistency that I am near certain to draw one.
Doubling Season doesn't have that, so I added it's good friend Idyllic Tutor.
Here's the decklist I ended up with:
Lands (22)
4 Arid Mesa
3 Forest
2 Ghost Quarter
2 Mountain
2 Plains
3 Sacred Foundry
3 Stomping Ground
3 Temple Garden
Creatures (8)
4 Birds of Paradise
4 Noble Hierarch
Spells (30)
4 Ajani Goldmane
4 Chandra Nalaar
4 Chrome Mox
4 Idyllic Tutor
4 Naya Charm
2 Path to Exile
4 Sarkhan Vol
Sideboard (15)
4 Chalice of the Void
4 Engineered Explosives
2 Guttural Response
3 Krosan Grip
2 Path to Exile
Step 1: Ramp into a Doubling Season.
Step 2: Drop a planeswalker.
Step 3: Win the game.
I don't think it's Tier 1, but it's a nice little strategy. If you already play Extended, you'll have all the expensive cards, and people will often think you're playing Zoo until it's too late.
I'll have some basic testing of the deck up tomorrow, as well as the rudiments of a sideboard plan. Enjoy!