The tracker is accessible through the TCGplayer app, making it easy to check your collection on the go
"Dash [cost]" means "You may cast this card by paying [cost] rather than its mana cost," "If this spell's dash cost was paid, return the permanent this spell becomes to its owner's hand at the beginning of the next end step," and "As long as this permanent's dash cost was paid, it has haste." If you choose to pay the dash cost rather than the mana cost, you're still casting the spell
Whether its you doing it or an opponent matters little
Now players have an extra element to think about when strategizing their attacks on opponents or plans to quest for Lore points
As design philosophy has changed and they have added more value to cards (including lands), card advantage has become less of a constraint, and being constrained as mana has become the games core constraint
The instant I saw the card, I immediately began brewing some vile combos to use in a variety of formats Standard, Commander, you name it