Asymmetric multiplayer
Also said as One versus many, 1v4, Asymmetric PvP
The two sides play by different rules, with different abilities and different goals, such as one strong hunter against a team of weak survivors.
Each side gets a fantasy that a mirror match cannot offer. It is also hard to balance, because no symmetry protects you: you can only tune it, measure who wins, and tune it again.
Say it
“One hunter against four runners, and I want the hunter to win 50% of matches at every skill level. Give the hunter 115% of runner speed to start, and report win rate by rank each week.”
Where you’ve seen it
Dead by Daylight has one Killer against four Survivors, who must repair five of seven generators to power the exit gates, while the Killer hunts them down.
Not to be confused with balance
A symmetrical game is balanced by default, since both sides are the same. An asymmetric one is not, and small changes can move it a long way.