Dubious Challenge
Oracle Text
Look at the top ten cards of your library, exile up to two creature cards from among them, then shuffle your library. Target opponent may choose one of the exiled cards and put it onto the battlefield under their control. Put the rest onto the battlefield under your control.
Card Rulings
9/20/2016 The creature cards you exile are face up. Your opponent can see them while deciding whether to take one and which to take.
9/20/2016 You may choose to exile only one creature card. If you do, the target opponent chooses who gets the card.
9/20/2016 You may choose to exile no creature cards, even if there are one or more among the top ten cards of your library.
9/20/2016 The cards that you look at but don’t exile never leave your library. They’re shuffled along with the rest of your library.
9/20/2016 In a multiplayer game, you must choose the target opponent before you look at your top ten cards and decide what to exile.
edit- Actually it really doesn't work since you'd then be forced to put Phage onto your battlefield.
However, this card could see play. There is a heavy theme of investment in this set, rewarding you for putting time and effort.
For example, if you have Panharmonicon in a deck based around ETB abilities, it changes which card is better. Your opponent will have a tough choice, as even if they pick the card that has more value for them, they might not be forcing you to get the short end of the stick.
Another example is energy-dependent cards. Unless your opponent is also playing an energy deck, they'll likely get one use out of the card they pick, but you can get many uses. That Architect of the Untamed would be useless to them, but you might be able to dump a 6/6 on the field right away, so you win out regardless of what your opponent picks.
Any form of unsummon gets your creature back and into your hand. A lot better than where it was in your deck. It may be a 2 card process, but I see this as a tutor for 2 creatures.
If this was a true tutor it might be worthwhile as a Gifts Ungiven-esque effect, but its just the top 10 cards. Lots of things have to align to make your scenario pay off.
1. Mana cost of 3G
2. Look at some number of the top cards of my library
3. Pick creatures from there
This is Wizards trolling us just as Collected Company is rotating out of Standard. I can't see any other explanation for this card.