Flicky

A game made by Sega and released in 1984 for arcades and Sega's SG-1000 console, and subsequently ported to several computers and the Sega Genesis. It predates Sonic by seven years but was designed by a future member of Sonic Team, namely Youji Ishii. It also inspired the Sonic game Sonic 3D: Flickies' Island (also known as Sonic 3D Blast).

The player's objective in each round is to run around as Flicky, collecting all of the Chirps in the stage, and then to run to the exit. The enemies Tiger and Iggy will try to scare away the Chirps and hurt Flicky.

This game contains examples of these tropes:

 * All in A Row
 * Bonus Level: In which Flicky must catch the Chirps with a net before they drop to the bottom of the screen.
 * Cats Are Mean
 * Compilation Rerelease: The Genesis/Mega Drive version has been included in many compilations, starting with the 4-in-1 Classic Collection for the same system, and later with both versions of Sonic Mega Collection, and then Sega Genesis Collection and Sonic's Ultimate Genesis Collection. The Japan-only Sega Saturn compilation Sega Ages had the original arcade version.
 * Cool Shades: Some Chirps are radical 80's kids and wear them. They'll run nonstop if separated from Flicky.
 * Easter Egg: Every level has an orange window near the goal. A girl in a bikini appears in it if certain scoring requirements are met.
 * Endless Game: There's a harder second loop, which the game will repeat on subsequent successful playthroughs.
 * Excuse Plot: Your chicklets are scattered throughout the levels, and you have to save them from the cats and lizards.
 * Homage: Gunstar Super Heroes would pay tribute to Flicky at one point in its first stage, where you have to lead a pack of chicklets to a door.
 * One Hit Point Wonder
 * Spiritual Successor: Sonic 3D Blast.