I'm out of the loop, but my friend had a nasty deck years ago with Phyrexian Obliterator, though it doesn't necessarily add value beyond itself like some of your other choices (Dauthi Voidwalker looks wild)
Vigilance is missing on purpose because it seemed odd to grant the ability when it already had the ability to untap itself
Heroes of the Realm cards have a very distinctive back , whereas Happy Holiday cards have a silver border and have written Happy Holidays on them
Electrostatic Pummeler - 1 Way too energy hungry
Having the right answer to combo, wiping the board and starting fresh, and filling your deck with great enter the battlefield creatures are all hallmarks of the guild
A few final tips to help your deck sing: Remember to value the board-wide protection options first, as they can be used as single-target protection in a pinch Remember to get that protection effect also onto other cards, and even on lands (like Sejiri Shelter)