This deck is a poor implementation of a bad idea.
Renown cards that are based on the cost of the card that triggered it use the total cost of the spell including amplify (it does not work this way for weapons with neither Spellcraft nor Clutch of Talons' amplify being included). This is best abused by cards that can target multiple units (
Bottoms Up and
Mighty Strikes) because if you have 3
Glacier Shapers on the board you can use one cast of
Bottoms Up to trigger all of them. More importantly this allows you to hit obscene power amounts of power with
Ruckus Rouser and then cash in that power to win the game with
Clutch of Talons,
Brilliant Idea,
Shingane Firebrand, or with enough power you can kill your opponent directly with
Xo of the Endless Hoard's ultimate.
Quicksilver Mirror allows you to deploy multiple renown cards without triggering them - this is a ridiculous idea, but much of the success of the deck is already predicated on your opponent not doing anything so it's not a problem.
Yushkov, the Usurper is included because the single turn of ramp can be sufficient to start a
Ruckus Rouser chain or pull off a giant
Brilliant Idea or
Clutch of Talons with a
Dune Painter on the field.
Mirror Image is an amazing Renown trigger in general - if you've never tried it with Hojan I highly recommend it.
Why Glacial Shaper, Downpour, or Bottoms Up?