There you can find decklists being shared, new decks being brewed, championships and metagame discussion (and the popular which card should be banned now rant as well)
This design is whats commonly referred in Magic: The Gathering terms to as a 'mana dork' - a creature whose sole job is to sit there and churn out mana for their controller to amass
That means from the stack by Dissipate, from in play like Swords to Plowshares, or from graveyards like Bojuka Bog
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Sisays great for decks that want to assemble a particular combination of legendary cards, like Gaea's Cradle, Nykthos, Shrine to Nyx, or Elspeth, Sun's Champion