It would be easy to construct a Standard environment where Desecration Demon is crap (such as he was in INN-RTR when Lingering Souls was legal,) or where Prime Speaker Zegana is a chase mythic
On the other hand, companions have been problematic for various reasons, with five of them being currently banned across MTG 's formats
This archetype is very unique, revolving around a mechanic that would usually be completely self-destructive in a TCG: milling, or discarding one or more of your own cards from your deck
During each of your Standby Phases, detach 1 Xyz Material from this card or take 2000 damage
It's also worth noting that the card is from Upper Deck's 1991 printing, and his actual playing days on grass didn't take place for a few years, making the example an interesting piece of sports history for a variety of reasons.
You're at a point where you want to find out what they're worth so you can continue collecting or buy yourself something nice