Nasty card flow in one smashing fun time but the cost keeps It out of my Top Ten proper
Whenever your opponent casts their first non-creature spell each turn, you may draw a card, unless your opponent pays X (where X is Esper Sentinel's power)
Oh, and since this isnt legendary it becomes one of the nastiest clone target for any deck that can use energy or that needs to convert high storm count turns into wins in an unusual color identity
You potentially can also use the front side of Invasion of Shandalar to return massive finishers like Portal to Phyrexia or Atraxa to your hand, flip Invasion of Shandalar, and drop them into play on future turns, which sounds powerful if you can find the time to get it set up
Unfortunately for Inteleon, it's the cheapest of the three starters, so it loses the friendly rivalry among its fellow starters, but at around ten dollards, this card is still a great art to own