While the deck does have a tutor effect in The Eleventh Hour, thats certainly not enough to ensure you will see the cards you need, especially in a deck that exiles cards on many effects
For starters, the commander gives you 1 life every time a creature enters the battlefield
If thats all this was, this would be a decent card
Regardless, lets go ahead and jump right in
That isnt as much to say beyond it feels you can win in a cave with a bucnh of rocks when you have Underworld Breach in play
What I came up with is that purple takes one spell effect from each of the other non-green colors: from white - enchantment removal (worse than white) from red - direct damage (worse than red) from blue - countermagic (exclusive) from black - edicting (exclusive) If purple had been around from the beginning, it would definitely have at least one exclusive ability, so blue doesn't get any countermagic at all in this set