I made it to mythic and wanted to make a fun deck to play around with and this one seems to be faring better than expected.  Bonus points for using Shimmer Dragon, which is a juicy finisher.  Though far from a tier 1 deck, this deck has beaten top decks.

Basic Premise:

The goal is to ramp up early with Growth Spiral and to try and get a turn 3 Smothering Tithe.  From there, you have a couple directions to go into depending on whats in your hand.  I'll discuss some decisions and card choices below:

1) Get Shimmer Dragon on the field.  This card is a fantastic draw engine and with 4 artifacts on the field (the tithe tokens are considered artifacts) will resist being stolen or destroyed by anything other than board wipes or forced sacrifices.  Then smash face, a 5/6 flyer with hexproof is nothing to sneeze at.

2) If you have enough mana/treasure tokens, use Fae of Wishes to fetch stuff relevant to the situation. 

3) Play Emergency Powers to rack up those treasure tokens with Smothering Tithe on the field.  Ideally, you'll draw into your Fae of Wishes and will be able to play things out of your sideboard with no color restrictions.  Or, you'll be able to cast Shimmer Dragon if you played Emergency Powers on your turn (without paying for the dragon) and will already have enough treasure tokens to have the dragon enter with hexproof.

4) Uro, Titan of Nature's Wrath has a couple purposes.  a) ramp mana b) gain life, which is especially good during more aggro matches and will help you live long enough to cast the bigger stuff c) big body that can be used to block/finish someone d) his Escape ability can be used to remove stuff from your grave that you do not want to recycle with Emergency Powers such as excess lands, Growth Spiral, or other cards that don't work as well in this matchup

Sideboard:

The sideboard is largely made up of different answers to different situations, including board wipes, Planeswalker removal, artifact/enchantment/creature removal and is otherwise self-explanatory. i'll highlight a few options that can be used to win the game.

1) Tezzeret, Master of the Bridge is a win condition.  Once in play, his +2 ability deals damage to opponent and heals you for the amount of artifacts you have in play, which includes the treasure tokens.  Also, he gives your creatures affinity for artifacts, so if you play him first, you may have enough mana to also play Shimmer Dragon. 

2) Underworld Dreams combos with Emergency Powers, hitting opponent for 7 to face when they draw a new hand.  Ob Nixilis, the Hate-Twisted is another option and may even work better at times because he can also be used to destroy creatures.  I rotate them in and out depending on what i'm seeing in the meta.  Right now, i'm facing a lot of aggro red or very control heavy.  So I prefer the cheaper option and one that is tougher to remove.

3) Kiora Bests the Sea God is a finisher.  

4) Mass Manipulation and Expansion//Explosion are finishers

Mathups:

I have not had too long to test this deck.  It was built yesterday and i've played maybe 10-15 games on ladder with it after the initial few to get an idea of how it plays.  If you're looking to grind ladder, this is not the deck for you.  This is more of the "i'm tired of playing straight up aggro/control decks and want to play one that lets me explore some fun win conditions/interactions."

1) RDW and other aggro: Glass Casket is a good removal spell that also counts towards Shimmer Dragon's abilities.  Don't be shy about using fae of wishes for an early chump blocker.  No surprise that Teferi, Time Raveler is a great stall card.  Use the draw cards to search for Shatter the Sky.  I'd toss Uro if you don't have early removal.  Growth Spiral has been my preferred ramp spell vs aggro since you can get that 4th land for the board wipe.  All in all, as with most decks, it really depends on how your early game plays out to determine win.  If you can keep his board from blowing up, using this deck's stall cards to get a board wipe, you will generally win.  Deputy of Detention is another option for removal.  I havne't tried it in this deck, but maybe instead of the two Glass Casket and an uro.

2) Fires varients: This is probably the tougher decks to face since this deck isn't fast enough to rush their life down and isn't control heavy enough to effeciently counter their plays.  If you can get a smothering tithe early enough, thats the best chance to win since you will benefit from all of their draws.  Use Teferi's ability to set up a Shatter the Sky on their turn to clear the board.  The good thing is that the Shimmer Dragon is beefy enough to stop the Cavalier of Gales and Kenrith, the Returned King and trade with the Cavalier of Flame.  If you can get the tithe early enough you can use the sideboard removal to control the planeswalkers.  Ultimately, this is a tough matchup.

3) Simic Ramp: I'd say this is 50/50.  depends on which of you can effeciently ramp into your threats.  The biggest threat from simic ramp is the Agent of Treachery.  If the simic ramp player knows what they're doing, they will target the tithe.  On the other hand, if its late enough and your Shimmer Dragon is hexproof, you can smash face.  

4) Midrange decks: if the decks don't have heavy answers against sorcery removal and your tithe can stay and rack up the treasure, you're golden.  I've had good wins vs. the enchantment decks, mono-black, adventures.  Temur adventures is the tougher varient to face, but even then.  they can't bounce all of your tokens and they don't usually run counters, so you can pretty much run rampant some games.

Closing Notes:

I am not a pro gamer, so I have no idea if this is the most optimal varient, but i've played maybe 5 different versions of this deck on these forums and this version has worked the best and the most consistently for me.  The bonus has always been using cards that aren't as heavily played like Shimmer Dragon and Tezzeret, Master of the Bridge.  I hope you have fun and i'm open to suggestions on how to make this better.