What do the question marks mean for attack points and defence on a Yu-Gi-Oh card?

The question marks ("?") on a Yu-Gi-Oh! card for attack and defense points indicate that the monster's attack or defense points are variable. This means their exact value is not fixed and can change depending on certain factors.

Here are the most common reasons for question marks:

* Effects: The monster's effect might specify how its attack or defense points change under certain conditions. This could involve factors like:

* Card types in the Graveyard: "This monster's ATK is equal to the number of Spell/Trap Cards in your Graveyard."

* Monster on the field: "This monster's DEF is equal to the ATK of another monster you control."

* Other game states: "This monster gains 500 ATK for each Spell/Trap Card your opponent controls."

* Special summoning conditions: Some monsters have their attack and defense points determined when they are Special Summoned. The question marks represent this variability.

* Pendulum Monsters: Pendulum Monsters have their attack and defense points determined by their Pendulum Scale. The question marks indicate that they are not fixed.

In short, question marks on a Yu-Gi-Oh! card indicate that the monster's attack and defense points are not static but are subject to change based on various factors.