OB53 Update Notes

OB53 introduced the "Undersea Mystery" event mechanics. The match-start plane became a whale, and an entrance to the Underwater Kingdom appeared at Bermuda's Nurek Dam, with an interactive sword statue that grants high-level loot. The High-Level Loot Zone became the Aquatic Zone, surrounded by water walls that deal no damage or slow (but bullets pass through), and Fishing Lagoons were scattered across the map, granting buffs that follow the fisher — even if you eliminate the player who fished.