Released in 2018 by solo developer Mystman12, Baldi's Basics in Education and Learning is a first-person horror game disguised as a cheerful 90s educational title. You're dropped into a procedurally laid-out school and tasked with finding 7 notebooks. Baldi walks the halls calmly at first — but every time you answer a math problem incorrectly (and one per notebook is designed to be unsolvable), he gets faster and more aggressive. The game's deliberately cheap visuals, surreal NPC cast, and escalating dread made it a massive viral hit shortly after release.
Move with WASD, look with the mouse, and interact with E. Notebooks are scattered through the school — solve the three math problems in each one. After every wrong answer, Baldi's ruler swings get faster. Use items found around the school (energy drinks, school hall passes, BSODA) to slow or redirect Baldi and the other NPCs that will also interfere with your escape.