Games like Great Fly Invasion!
Games like Great Fly Invasion! include Vampire Survivors, Planes, Bullets and Vodka, Touhou Mystia's Izakaya, Timberman, and Cyberhunt. We matched them by the tags players give Great Fly Invasion! on Steam (Time Management, Casual, Immersive Sim, Shoot 'Em Up, and Arcade): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Pixel Graphics · 2D · Casual

Planes, Bullets and Vodka
Shared: Casual · Shoot 'Em Up · Arcade

Touhou Mystia's Izakaya
Shared: Casual · Time Management · Pixel Graphics

Timberman
Shared: Casual · Pixel Graphics · 2D

Cyberhunt
Shared: Casual · Shoot 'Em Up · Arcade

To The Core
Shared: Casual · Arcade · 2D

DAVE THE DIVER
Shared: Casual · Pixel Graphics · Singleplayer

Bit Blaster XL
Shared: Shoot 'Em Up · Arcade · Casual

Peggle Deluxe
Shared: Casual · Arcade · 2D

Shower With Your Dad Simulator 2015: Do You Still Shower With Your Dad
Shared: Arcade · Casual · 2D

pureya
Shared: Casual · Arcade · 2D

BALL x PIT
Shared: Arcade · Shoot 'Em Up · Pixel Graphics

112 Operator
Shared: Casual · Time Management · Immersive Sim

Shelldiver
Shared: Casual · Arcade · 2D

LUFTRAUSERS
Shared: Arcade · Shoot 'Em Up · 2D

People Playground
Shared: 2D · Destruction · Singleplayer

DJMAX RESPECT V
Shared: Casual · 2D · Arcade

Airscape - The Fall of Gravity
Shared: Shoot 'Em Up · Casual · 2D

Papa's Freezeria Deluxe
Shared: Time Management · Casual · 2D

Papers, Please
Shared: Pixel Graphics · Dystopian · Singleplayer

20 Minutes Till Dawn
Shared: Shoot 'Em Up · Casual · Pixel Graphics

SUPER CHICKEN JUMPER
Shared: Arcade · 2D · Pixel Graphics

Razortron 2000
Shared: Casual · Arcade · 2D

Punch Club
Shared: Time Management · Pixel Graphics · Arcade