Whenever a land's ability causes you to add one or more mana of the chosen color, add an additional one mana of that color
Like The Meathook Massacre, it's unsurprising that this one has found its way into Historic as well as Standard
When Peer into the Abyss resolves, you are very likely to draw at least 30 cards, and if your commander Starscream, Power Hungry is on the board and you are the monarch, you're definitely blowing up one opponent's life
Nature's Rhythm This -cost sorcery will put a creature with X cost or less on the battlefield from your library, and then you can do it again for X and four green with Harmonize
You get to manifest a card from the top of your deck, putting two +1/+1 counters on it and a trample token to boot, giving you a 4/4 for four mana, which is a fair exchange