Battle pass
Also said as Season pass, Reward track
A track of rewards you unlock by playing during a season, usually with a free line and a paid one. Dota 2's 2013 Compendium was the forerunner, and Fortnite made it the norm from late 2017.
It is a fairer deal than a loot box, since you know what you are getting and it has a known price. Its catch is the deadline, which turns a leisure activity into something like a work schedule, especially once a player has paid. Selling tiers near the end charges them again for the hours they ran out of. Make it hard to fall behind, or drop the deadline.
Say it
“Make the pass finishable in 40 hours over ten weeks at most, with no paid tier skips in the last two weeks. Once you own a pass it does not expire.”
Where you’ve seen it
Halo Infinite's battle passes do not expire, so you can keep working through one later. It shows that the deadline is a choice and the model works without it.
Not to be confused with season pass (old sense)
A season pass used to mean buying all of a game's planned DLC in advance. A battle pass is a reward track you work through by playing.