Why only Elf 4rtk has TIC-tac-toe?

Elf 4rtk can fly TIC-tac-toe. Genie 4RTK is a small multi-rotor high-precision aerial survey UAV, which is oriented to low-altitude photogrammetry applications. It has centimeter-level navigation and positioning system and high-performance imaging system, which is portable and easy to use, and comprehensively improves the efficiency of aerial survey. Only Elf 4rtk has tic-tac-toe because only Elf 4rtk can fly tic-tac-toe.