yugioh math deck Yu-Gi-Oh! Mathmech Circular - POTE-EN028 - Super Rare What happened to Mathmech decks?

(2021-07-23) A player may only have one dungeon in the command zone at a time

Then, return up to 1 active Character with a cost of 3 or less to the owner's hand

Because they're also machine type monsters, cards such as "Magnetic Mosquito" and "System Down" also hurt them (especially System Down, as it banishes Machines), and are the most common, exploitable, and obvious countermeasures to this deck since "System Down" can eliminate the presence of all Machine monsters on the field as well as those in the Graveyard (which the "Cyber Dragon" archetype are heavily reliant on as most monsters within it allow them to share it's name)

The rate is terrible because you need to pay at least 5 to start the destruction, and it only gets snow lands, of course, so thats a downside

In fact, that was arguably the block that helped recontextualize all three of these cards