Stompy decks in Magic: The Gathering have a new mechanic called Expend through the Bloomburrow Standard-legal set. Here's how it works.
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Casting big spells in MTG is important via the Gruul color combo, while Bloomburrow's new Expend mechanic provides additional value for those expensive spells.
For example, an Expend number of four requires you to spend four or more mana when casting permanents that turn. You can spend the mana on one spell or multiple spells. When you spend the four mana, the bonus is activated.
One of the best examples of the MTG Expend mechanic is through Muerra, Trash Tactician. The Rare Raccoon Warrior adds red or green mana for each Raccoon you control. Muerra also has the Bloomburrow mechanic with Expend four and Expend eight.
