While it works well, I've always felt Kiora, the Rising Tide played a bit too similarly to other "draw two, discard two" cards. Seasoned Cryomancer has a couple advantages in this regard: It has a unique effect that isn't "pure value", it's a human and it may get some value from the graveyard.
The biggest issue is the 1UU cost, particularly since it's much lower on power level.
I'm also interested on:
This is easy to trigger, versatile and playable enough on its own. It can be a way to diversify my recursive creatures, though I fear it might be too much of a second Vengevine.
Wow, wow, look at this! This has a lot of potential for Riptide cubes.
While this is meant to be a creature-based Displacer Kitten, I think it's not quite that. Rather, I think it's actually closer to Beast Whisperer, only with a more interesting effect. One of the problems with Whisperer is that you only have so many useful effects in your deck, often, you draw cards but can't actually close the game with them. Flickering Hound lets you reuse the effects you already have, effectively increasing the density of effects you can deploy in each game.
It seems to lend itself well to green but, while it works with Earthcraft and triggers on mana dorks, green doesn't usually have as many ETBs.
While it works with Earthcraft and triggers on mana dorks, I'm not sure Eternal Witness, Rishkar, Peema Renegade and Wall of Blossoms are the best targets for it.
Regarding power level, I'm glad it's not as good as Displacer Kitten. The Kitten is extremely binary, often winning the game if it sticks for a second too long. It just works with too much stuff, most notably mana-producing artifacts. However, I fear it can be worse than Enduring Innocence. They kept the 2/2 statline, too, which is likely to be a problem.
But flickering creatures is fun. It has that combination of openness and restrictions that make it interesting to use.
Triggering on all non-creature spells, its 1U cost and huge butt makes this far more playable than other similar cards we've had. I like it more than Stormwing Entity.
This is a good design. I can see it in lower powered cubes as a way to get certain powerful auras. It has that draft-like quality that I like.