Number Master: Run and merge

Number Master: Run and merge is a hyper-casual action game developed by KAYAC Inc. that gamifies basic arithmetic through a high-speed runner format. The objective is to navigate a numerical entity through a course, "absorbing" numbers that are smaller than the player's current value to increase their total. Conversely, colliding with a number larger than the player's results in an immediate failure, forcing a restart. The 2026 iteration features various environmental hazards, such as electric saws, jumping ditches, and crossable bridges, which require the player to balance spatial awareness with rapid mental calculations.

A hallmark of Number Master is its "Wall Breaking" endgame mechanic. Upon reaching the goal, the player's final number is used as "force" to break through a series of walls; the larger the number, the more walls the player can penetrate to reveal higher reward multipliers. The game utilizes an upgrade system where coins can be spent to increase the starting number or improve the money multiplier, though these are currently capped at 100 and 6.0x respectively. Professional observation of the 100 million+ download base indicates that the game's appeal lies in its "instant satisfaction" loop, though it is frequently critiqued for its heavy ad density and repetitive level design once upgrades are maxed.

The game's 2026 updates have introduced more "sensory" rewards, such as seeing "the world beyond the finish line" when breaking through the final wall. However, the community has pointed out that reaching the ultimate "777x multiplier" displayed in advertisements remains practically impossible even with maxed-out stats, leading to a sense of being "tricked" among the elite player base. Despite these criticisms, Number Master remains a leader in the "merge-runner" category due to its clean visual aesthetic and the absence of a traditional home screen, which facilitates an endless, friction-free gameplay experience.