First, you cannot cast them unless you have lands already
From a rare land cycle that sees play in Commander to cards like Ledger Shredder that are seeing play in Pioneer, the set has competitive cards and expensive pick-ups for both strategists and collectors alike
Take another look through the Card Image Gallery, make sure you're preregistered at your local store, and get ready to come out to the Prerelease and have fun
At the time of writing, nonfoil copies of Ancient Tomb found in Collector boxes seem to be selling for between $60-65
For example, Bahamut might burn the board then stick around as a 7/7 flyer
Your main goal is to swarm the board with creatures, drop Sephiroth to farm cards, and hopefully transform Sephiroth immediately