Old Frogs Kenrith already seems to be a pretty nice fit for my Frog army, but there are some older Frogs I've thrown into the list that will work nicely with his Royal Highness
Once per turn, during either player's turn, when your opponent activates a Spell/Trap Card, or monster effect: You can negate the activation, and if you do, destroy that card
Can You Cast Adventure Spells from the Graveyard
I would say its undervalued for what it is, but probably still too niche
Sellers are generating revenue not by finding old cards, but by printing new, unique ones
However, if your Zoodiac Xyz Monster survives till the next turn, after Xyz Summoning Zoodiac Broadbull to add Zoodiac Thoroughblade from deck to hand, you could use it to Xyz Summon Zoodiac Chakanine , revive a Zoodiac monster, and use both to Link Summon Missus Radiant