It can be used to protect your own creature as well as to recycle good ETB triggers from cards like Mulldrifter, Solitude, Fury, you name it
Magic is only going to add cards after all, and Ive always been happy to see something useful in my boxes Ive forgotten I own
Provided you bake in scry lands, surveil lands (and fetchlands to grab them on other folks turns), and other ways to Scry or Surveil at instant speed, you can multiply those free casts
Check out Stephen Menendians deck from the 2011 Vintage Championships: "Stephen Menendians 2011 Vintage Champs Deck" Creatures (10) 3 Trygon Predator 4 Dark Confidant 1 Blightsteel Colossus 2 Vendilion Clique Spells (36) 1 Ancestral Recall 1 Brainstorm 1 Hurkyl's Recall 1 Mystical Tutor 1 Vampiric Tutor 4 Force of Will 4 Gush 4 Spell Pierce 1 Demonic Tutor 1 Merchant Scroll 1 Ponder 1 Time Walk 1 Tinker 1 Yawgmoth's Will 4 Preordain 1 Fastbond 1 Black Lotus 1 Mox Emerald 1 Mox Jet 1 Mox Pearl 1 Mox Ruby 1 Mox Sapphire 2 Sensei's Divining Top Lands (14) 1 Island 1 Flooded Strand 1 Misty Rainforest 1 Polluted Delta 1 Volcanic Island 2 Tropical Island 3 Underground Sea 4 Scalding Tarn Sideboard (15) 1 Ancient Grudge 2 Ingot Chewer 4 Leyline of the Void 2 Lightning Bolt 1 Mountain 2 Pyroblast 1 Red Elemental Blast 1 Tormod's Crypt 1 Yixlid Jailer Trygon Predators role is clear in Vintage: munching on Moxes
If Xenagos, God of Revels is already on the battlefield, then Bello enters
