One of the most common is the +1/+1 counter, but counter markers are also used for planeswalker loyalty, to charge abilities, and for specific card qualities
Even though Endurance is mostly played as a sideboard card, basically any green deck in the format plays it to fight graveyard based strategies
As a standalone set, we're probably being a bit kind to it, placing it this high given its lack of impact on the current meta, but if we look forward to the next two or three sets, we see a lot of potential for some great storytelling, amazing new cards, and stunning artwork
On Pokemon cards, theyre used for: Pokemon names: (Pikachu), (Charizard), (Mew) Foreign loanwords in card effects: (Damage), (Energy), (Bench) If you see angular text at the top of the card, thats the Pokemons name in katakana
The catch is, you need to pay 5 mana on your next upkeep or you lose the game