­Mountain + Dread of Night

Huh, I don't recall colour hosers being quite that efficient; but obviously my recall is faulty.

So, red hosing. Red's enemies are white and blue. White does armies and buffing, blue does weird shit and flying.

Red doesn't usually do anti-flying (other than 'I get a few flyers too - and mine tend to be bigass dragons') so a weird-shit hoser.

Red gets those from time to time; mainly because it too gets to do strange stuff with instants and sorceries.

So.. how about overload. Overload is mainly "Fork all of the things!" but can also be used as a way to mess up a carefully crafted blue strategy. "And now I need to flicker, um, oh crap"

And I like Grip of Chaos-alot.

Plausibly mythic? Let's say rare, though.

What does Incremental Growth do? "another each"?

Making even less sense, Vines of Vastwood: "can't be the each..."

And not that it could even attempt to do much under this (Auras?) but Swerve reads ridiculously: "Change the each of each spell with a single each."

­Phyrexian Purge: "Destroy any number of each creatures. CARDNAME costs 3 life more to cast for each each."

Yeah yeah yeah; it's obvious what it's meant to do :)

Anyway, your last example is:
Pay 3 life per each: ... which actually kinda works.