Diamond shapes appear on the grid. Cyan = Slow Time, Purple = Ghost Mode, Gold = Double Points. Each lasts for a limited number of moves.
Eat food in quick succession to build a combo multiplier. The multiplier resets if you wait too long between eating. Higher combos give significantly more points.
Every 50 points, the game advances to the next level and the snake moves faster. The speed increase is gradual, giving you time to adjust your strategy.