With The Lost Caverns of Ixalan, these were available in set boosters, but not in draft boosters
1 in 5 of those common dual lands are traditional foil
Protect your collectible cards from scratches, dust, and wear with these high-quality holographic protective card sleeves
At time of writing, there are only two known commons that reward this unnamed mechanic: Arena Trickster, which turns from an unexciting Hill Giant into a Rampaging Baloth (and can continue to grow), and Naiad of Hidden Coves, which allows you to play two Vexing Gulls on turn four
There are occasions these make for great board cards but overall they are not the kinds of thing your deck is trying to do
It's enjoyable, but it'd be even more so if there were just a few more competitive cards - or fewer cards that have nothing to do with Inventors