For the first few years of its production, Magic: The Gathering featured a small number of cards with names or artwork with demonic or occultist themes, in 1995 the company elected to remove such references from the game
The normal cards were completely fine, but the foiling effect on the other cards seemed to be magnified by the plastic (cheap) sleeves I was using
Subsequently, as u/Razortail mocked in their post, theres heavy skepticism around new artificially rare cards
Myr offer a generally low casting cost for these decks coupled with the two most common myr modes: mana production, and combo synergy
The number of card types is checked again as the trigger resolves
The deck is loaded with the best artifacts, and plenty of ways to get them back from the graveyard to keep the action going all game