The quote I remember was this: "Paincast is the scary part of affinity." It was what we call a "win when you're ahead" mechanic, which means that it is often very useless when you most need it and meaningless when you are able to use it
Aegis Turtle Ambitious Augmenter Ambling Stormshell Ancient Adamantoise Angler Turtle Archelos, Lagoon Mystic Armored Whirl Turtle Bedrock Tortoise Blossoming Tortoise Calcite Snapper Casey & Raph, Hotheads Cold-Water Snapper Colossal Skyturtle Daring Thunder-Thief Dark Leo & Shredder Definitely Not a Turtle Don & Leo, Problem Solvers Don & Raph, Hard Science Donatello, Gadget Master Donatello, Mutant Mechanic Donatello, Rad Scientist Donatello, Turtle Techie Donatello, Way with Machines Donatello, the Brains Donnie & April, Adorkable Duo Dragon Turtle Fecund Greenshell Giant Tortoise Giant Turtle Gorex, the Tombshell Heroes in a Half Shell Hexbane Tortoise Horned Turtle Jennika, Bad Apple Big Sister Kappa Cannoneer Kappa Tech-Wrecker Kogla and Yidaro Leonardo, Big Brother Leonardo, Cutting Edge Leonardo, Leader in Blue Leonardo, Sewer Samurai Leonardo, Worldly Warrior Leonardo, the Balance Lita, Little Orphan Amphibian Meandering Towershell Metalhead Michelangelo, Game Master Michelangelo, Improviser Michelangelo, Mutant BFF Michelangelo, On the Scene Michelangelo, Weirdness to 11 Michelangelo, the Heart Mikey & Don, Party Planners Mikey & Leo, Chaos & Order Mikey & Mona, Mutant Sitters Mistford River Turtle Phantasmal Shieldback Prehistoric Turtlesaurus Quandrix Cultivator Raph & Leo, Sibling Rivals Raph & Mikey, Troublemakers Raphael, Most Attitude Raphael, Ninja Destroyer Raphael, Tag Team Tough Raphael, Tough Turtle Raphael, the Muscle Raphael, the Nightwatcher Riptide Turtle Sailors' Bane Scuttlegator Shellephant Silburlind Snapper
If you want something a bit more catch-all for any deck, however, try Duplicant and Meteor Golem
The goal is to hit a critical mass of creatures in the graveyard so that 1) a resolved Haunting Misery is lethal and/or 2) a resolved Songs of the Damned + Drain Life is lethal
