Games like .G
Games like .G include Bit Blaster XL, Orbt XL, Vampire Survivors, A Dance of Fire and Ice, and Peggle Deluxe. We matched them by the tags players give .G on Steam (Difficult, Casual, Score Attack, Bullet Hell, and Arcade): closest matches first, and among equally close ones the better-known games.

Bit Blaster XL
Shared: Difficult · Bullet Hell · Arcade

Orbt XL
Shared: Difficult · Arcade · Score Attack

Vampire Survivors
Shared: Bullet Hell · Casual · Singleplayer

A Dance of Fire and Ice
Shared: Difficult · Singleplayer · Arcade

Peggle Deluxe
Shared: Casual · Arcade · Singleplayer

Geometry Dash
Shared: Difficult · 2D · Singleplayer

Bloons TD 6
Shared: Casual · Singleplayer · Family Friendly

Planes, Bullets and Vodka
Shared: Casual · Bullet Hell · Arcade

Timberman
Shared: Casual · Difficult · Arcade

Super Hexagon
Shared: Difficult · Arcade · Singleplayer

Zuma's Revenge!
Shared: Casual · Singleplayer · Difficult

FTL: Faster Than Light
Shared: Difficult · Singleplayer · Sci-fi

Brotato
Shared: Bullet Hell · Singleplayer · Sci-fi

Touhou Tenkuushou ~ Hidden Star in Four Seasons.
Shared: Difficult · Bullet Hell · Singleplayer

Space Rock Breaker
Shared: Casual · Arcade · Singleplayer

Feeding Frenzy 2 Deluxe
Shared: Casual · Arcade · Singleplayer

Enter the Gungeon
Shared: Bullet Hell · Difficult · 2D

Plants vs. Zombies GOTY Edition
Shared: Casual · Singleplayer · Family Friendly

DJMAX RESPECT V
Shared: Casual · Singleplayer · Difficult

Diamo XL
Shared: Difficult · Arcade · Casual

pureya
Shared: Casual · Arcade · Singleplayer

Geometry Wars: Retro Evolved
Shared: Casual · Arcade · Bullet Hell

Seraph's Last Stand
Shared: Casual · Bullet Hell · 2D

SUPER CHICKEN JUMPER
Shared: Difficult · Arcade · 2D