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Slide the top packet to the right and the bottom packet to the left
Put X +1/+1 counters on target creature, where X is the number of lands you control
This is to say that, despite the cost that each draw minimally impacts the composition of the rest of the deck, this deck probably has better mana than a 60-card deck with one less color (Im not sure how problematic needing to fetch four colors instead of three will actually be to how games play out)
Historically, the play rate (how much of the metagame share a deck has) of those decks has been low enough that it hasn't been an issue
Every time one of your dragons attacks, you get to tap down a nonland permanent your opponent controlsand it stays tapped through their next untap step