Throughout the course of the event, it has become clear that Extinction is one of the Modifiers needed to have a hope of breaking into the top 1% of players. However, I realized just now that there is one specific modifier that makes Extinction unavailable if you switch it on as a Challenge Modifier: [b]Battlefield Promotion[/b]. For whatever reason, because Battlefield Promotion allows enemies to be promoted if they defeat a player, it makes the Player Stake Extinction unavailable to choose as a Modifier, and vice versa, even though Promoted enemies naturally spawn in the game. So, for those aiming for 1% ranking and the Emblem, avoid applying Battlefield Promotion so you can apply Extinction.