The key component to this is that Legolass Quick Reflexes has split second, making it so long as it is on the stack, no one can cast spells or active abilities in response unless that ability produces mana
Decks that contain three or more colors and only have basic lands often struggle to find the right lands to cast their cards
Based on the latest market prices tracked on TCG Stacked, a foil copy of Damnation is worth about $43.03 USD
High Utility, Low Price Veteran Explorer Chasm Skulker Hushwing Gryff Windborn Muse Progenitor Mimic Swords to Plowshares Beast Within Cultivate Kodamas Reach Sylvan Reclamation Seeds of Renewal Rites of Flourishing Empyrial Plate I remember a few of these being more in the value category, but they were reprinted enough times in the intervening years to drop, which is a great thing for the players
That means it might not net you that much mana and you might not have much to spend it on when it does, and, as mentioned, two mana is an enormous amount to hold up
