Locked and Loaded is a Brain Buster in Plants vs. Zombies 2 and Plants vs. Zombies Online where the player has to use the pre-selected plants given to them to defeat the zombies. Before the 1.7 update, it was unlocked with four keys in Ancient Egypt and Pirate Seas, and five keys in Wild West. The player would receive a star after completing a level without losing any lawn mowers, though that was not a requirement after beating the level. After the 1.7 update, Locked and Loaded levels are placed like other level on the revised map, but have the requirements regardless of the number of times played. In addition, they are no longer referred to as "Locked and Loaded"; instead, they are named like other levels, and each world had a Locked and Loaded level removed. In the 1.9 update, the game removed the requirement on all levels with objectives to not lose any lawn mowers, including Locked and Loaded levels.
The Roman numerals are the level numbers before the 1.7 update for Ancient Egypt, Pirate Seas, and Wild West, but is used for disambiguation purposes for the remaining worlds. The parentheses show where the level is located after the 1.7 update, or if the level is removed in the update altogether.