PrintMTGs proxy/playtest cards are designed around that in-sleeve consistency idea: standard MTG sizing, familiar feel, and predictable finishing so your deck doesnt end up with one card that behaves like its trying to get caught
Break through The Line seems unplayable, so don't try to be cute and make it playable
Urza, Lord High Artificer Urza, Lord High Artificer is one of the best Magic cards in any list it qualifies for, from best blue commanders to best artifact commanders
Fifth Dawn Helm of Kaldra Helm of Kaldra is part of a three-card Equipment mega-cycle, with one card in each set of original Mirrodin block
Wizards has defended the incomplete reminder text by pointing out that it's not the first keyword that you have to read the rules to fully understand, and that casual players will assume it works because they assume everything works, while experienced players are all tapped into the data stream and will have heard the clarification before the Prerelease
Le Pines classic Red Deck Wins strategy pays off in this meta