How Lakitu throws Spiny Eggs in Super Mario Bros. is due to a glitch, not the intended behavior
Here’s something very interesting about the original Super Mario Bros. As it turns out, the manner in which Lakitu throws Spiny Eggs at players is unintentional. After many years, fans have discovered that he attacks with no horizontal movement due to a bug; it was instead supposed to be based on a few factors, like Lakitu’s speed and the player’s position.
The Cutting Room Floor explains:
The Spiny eggs are thrown by Lakitu in a simple way, with no horizontal movement whatsoever. However, this is not the intended behavior; it’s actually the result of a bug! The eggs are supposed to be thrown out relative to the player’s speed, Lakitu’s speed, the player’s position, and a pseudo-random value, as well as bounce off of any blocks or walls that they hit on the way down.
Here’s a comparison of the two versions of the Spiny Egg throwing for further clarification:
