It's quite mathy, but he goes into a great deal of detail and explains his rationale, while not ignoring the realities of the game (there are one-mana Cycling cards, cards that fetch lands, cards that tap to add mana which aren't lands, and more.)
This can +2 to draw a card and scry two which is nice card flow, and then -3 to exile the top card of your library and then make a number of 1/1 flyers equal to the mana value, which is also very strong in Type Four with its elevated casting costs and low land count
If so, let us know in the comments or on Draftsim's Discord
This Plains is actually part of a diptych, a single painting combined with the Forest he did for Lorwyn, and that was later cropped down to become two separate cards
Its essentially most of a Champions Helm but for a good deal less mana, especially if your creature is three or more colors