Nowadays there are a number of them retailing in the $20s, and Tectonic Edge can be purchased for even less
It became suspicious around the time Arknight appeared, and now there are too many people who can beat Castel without thinking about it, such as Castel for simple removal and Lightning for punching to death
Merchant Scroll enters the restricted list
Vampiric Feast, Soul Spike, Covenant of Blood, and Demonic Pact can go to the face but far more often kill creatures and thereby do impact the board
Trainer cards are a bit more complicated - they're basically support cards, with myriad different effects, and they're often the glue that holds a Pokmon TCG deck together
It's been a really nice card in the deck, but I've noticed that I've drawn it late game quite a bit, which makes it nearly useless when it comes into play tapped