Inked borders can be spotted fairly easily, as beta cards have a kind of 'double border', where only the out-most part of the border is completely black (there's also a white dot in the lower corners of the card between the borders)
Personally, though, I've long wanted to build a mountains-matter mono-red deck with cards like Koth, Fire of Resistance, but there aren't really enough relevant cards to make it work
They might see Taii Wakeen, Perfect Shot coming, but they'll need to scramble for hexproof or shroud before your Cone of Flame lands a triple kill, draws you three and completely flips the state of the board
If that power boost wasnt enough, every Ooze created by this spell has Trample, allowing you to overcome opponents defenses and overpower them with ease
Plus, it hides itself from hand removal which is one of the greatest weaknesses of playing wraths (cards that destroy all creatures on the battlefield)