You cant sacrifice the same Clue both to draw a card and to pay the cost of another ability (like Lonis, Cryptozoologists, which lets you sac clues to steal cards from your opponent)
Tana will grow each turn, you'll get a bigger Saproling army each turn and eventually your opponents will simply have to find an answer for her
(If you want to learn more about Gladiator, and you definitely should, go here!) And since Commander is about doing the most obviously over the top stuff Magic can hold, and Standard frequently becomes about the most blatantly pushed stuff anyhow, this is probably a use-ful theory exercise on watching for the right kinds of cards
We saw so many Lorcana fans come out and show up for the new Illumineers, help them trade, and explain what this is, Ryan Miller Miller credits the fans with making the Disney Lorcana TCG what it is today
Whenever you cast a creature spell of the chosen type, draw a card