"Have you ever noticed how some flavor text has no relevance whatsoever to the card it's on?" Preach, Ow, preach
Overall) I adore this on curve, Gruul, 4/4 4-drop that lets you drop another land on each of your turns for another go around the Landfall trigger
In those scenarios, Veil of Summer acts as a 1 mana hard counter by just stopping whatever your opponent is trying to do from previous mentioned options
Crucible of Worlds plus an additional land drop plus a way to mill yourself puts so many necessary effects into a single card that its hard to beat
The exact combo lines can be modular, but the core idea stays the same: get Lumra onto the battlefield, kill Lumra and/or sacrifice your Lands with the ETB on the stack, bring everything back, generate more resources than you spent, and repeat
Talrand, Sky Summoner is one of my favorite blue commanders for a deck entirely built from counterspells