The original Plants vs. Zombies has 20 selectable mini-games in its Mini-Games mode.
These challenges unlock as the player progresses through Adventure mode and provide short variations on the main lane-defense formula. Instead of simply surviving standard zombie waves, players may roll Wall-nuts, match plants, control a zombie attack, protect plants from unusual threats, or manage special rule sets. The mode is designed as a collection of compact experiments rather than one continuous campaign.
The number can be confusing because Plants vs. Zombies received version-specific content. Console editions, handheld releases, mobile versions, and later re-releases sometimes added, removed, or rearranged mini-games. The original PC-style set is commonly advertised as 20 Mini-Games, while the broader franchise has far more than 20 bonus challenges when exclusive content and later games are included.
Mini-Games are also distinct from Puzzle mode and Survival mode. Puzzle includes Vasebreaker and I, Zombie challenges, while Survival asks players to endure repeated waves with changing conditions. That separation is why the 20 figure refers specifically to the original game's selectable Mini-Games group.