The Zen Master is 900 Global's Axiom/Idol shape. For me the Master fits into that stronger symmetrical solid slot. Distinguishing the Zen Master from the Axiom/Idol is fairly simple. Here is the order from strongest to weakest. Axiom, Idol, Zen Master, Phaze II. Relatively speaking, the Zen is closest to the idol in overall strength, but it has just a tad more shape down the lane. I have enjoyed success with the Zen master on House conditions and flat reverse blocks. It's controllable enough to relax my hand and tumble it, but it doesn't sacrifice downlane motion when I get my hand around it like the Axiom does.

https://www.youtube.com/watch?v=W30jH6Y0Amw