In this set, 30 cards3 uncommons, 23 rares, and 5 mythic rareshave variant TARDIS showcase treatments
Yeah, when you have a jackrabbit start against a creatureless deck and you can use this to get your guys back, its pretty good, but against a good chunk of the format, it either does nothing (no enters the battlefield ability) or helps your opponent out as well by giving them back a ton of good utility creatures
If you throw a Helm of Awakening in there, you also get infinite mana
and if they receive enough damage, they die like normal creatures do
From Battle for Zendikar to Ixalan, every block has had at least some nod to white/black draining life (Dominaria has repeatable life loss, but no W/B drain card)
The most aggressive versions of U/G Merfolk probably wouldnt want to play Seafloor Oracle, but a token version that is looking to play a longer game with Deeproot Waters and Jungleborn Pioneer could be looking toward this card for card advantage