TL;DR: The Wilds Unknown top decks (Steelsong at 19%, Bounce at 16%, Ruby/Sapphire Items at 12%) remain the competitive backbone at Set 13 launch
19 Kwain is a simple group-hug machine that opens your deck up to plenty of blue-white synergies
The cards condition and version will affect its value
And then, as we already know, she can essentially Kiki-Jiki, Mirror Breaker one of your artifacts or dorks, making an artifact critter copy for a turn to smash
Look for details on card condition, whether the card has been graded, and any possible defects or damage
The problem with Devastation Tide is that spending all that mana and a card to wipe the board is all well and good but it doesn't deal with anything