The term originally meant something like being clever, crafty, wily, skillful, cunning, tricky, even rogueish or sly
Soft Score to Bracket Mapping 015 points: Bracket 1 (Exhibition) 1630 points: Bracket 2 (Core) 3150 points: Bracket 3 (Upgraded) 5175 points: Bracket 4 (Optimized) But the soft score alone does not determine the bracket
Now that quantities of Secret Lairs are even more limited, they will likely be sold at an even higher markup on the secondary market when, before, scalping Secret Lairs was a risk because most players simply bought them directly from Wizards when they could
Because it triggers from a mana ability and produces mana without targeting, Overgrowth creates a triggered mana ability
Also, sliver decks tend to go pretty wide so being able to tap all your creatures to draw a card, while also dealing massive amounts of damage each time is busted
Much like how Treasure Cruise stops being worth playing when you slowly and unreliably fill up your graveyard