Every Extend is series of puzzle shoot 'em up video games primarily developed by Q Entertainment. The series began with a 2004 freeware game of the same name (also known as E2) for Windows, which was a personal project by Kanta Matsuhisa under the "Omega" pseudonym. Q Entertainment discovered the game online and approached Matshisa to develop a remix version. The remix version was developed for the PlayStation Portable and was released in 2006, titled Every Extend Extra (or E3). In 2007, Q Entertainment developed and released a sequel on the Xbox 360 titled Every Extend Extra Extreme (or E4).

In Every Extend, players control a ship with the only ability to detonate itself. Stages begin with a set time limit and enemies appearing on screen in randomized patterns. When the player detonates their ship and an enemy is caught in its blast radius, the enemy will explode and have its own blast radius that other enemies can get caught in, causing a chain reaction. The goal is to destroy the maximum number of ships on screen by positioning and detonating at the right moment, setting off a chain reaction of explosions and earning combo bonus. The first enemy in a chain is worth 10 points and each successive blast doubles in value up to a maximum of 2560 points. Blowing oneself up takes away from one's overall 'stock' of lives. Additional lives are gained after a certain number of points have been obtained. The requirement to obtain lives increases after each new life gained.

Green enemies drop point bonus items that begin at 800 points, and if collected continuously without detonating or losing a life, they increase by an additional 800 points. Pink enemies drop quickens which raises the speed of enemies and spawn rate. Mini-bosses drop yellow items that grants 10-second time extensions. If the ship is destroyed without detonating, the player receives a 5-second penalty. Pulse bombs don't drop items or bonus but instead charge and detonate a wider range than normal once defeated. If the player runs out of lives or time, they lose the game

In Every Extend Extra and Every Extend Extra Extreme, each stage has its own unique music, background, enemy design, and bosses. It also adds varying explosion types to the Every Extend template, which can link chains in different ways, as well as a "charge" feature. By holding down the explosion button, players can charge the bomb; the longer the button is held, the larger the blast radius, expanding the possibility for chaining explosions. Quickens dropped by enemies increase the speed of both the player and the enemy, as well as the speed of that stage's music. Each stage is played out to a time limit, with a boss character appearing at a set point towards the end. Rather than attacking the boss directly, the player relies on destroying the required number of regular enemies near the boss to cause a 'hit'.

There are two modes in Every Extend: Light mode and Heavy mode. Light mode is easier and has a single boss at the end of the stage named "AKR-I-C-E". Heavy mode is more difficult and offers a boss named "KW MOTOR". An alternative boss named "A-BA HEDRON" can be encountered if the player manages to collect seven quickens, have over 5 lives remaining and accumulated over 800,000 points. Bosses are required to be defeated using only chain attacks

Every Extend Extra adds four new modes: 'Arcade', 'Caravan', 'Boss Attack', with the original Every Extend labeled as 'Original'. In Arcade mode players must work their way through the stage and defeat the boss at the end in order to move on to the next stage. Arcade mode is made up of seven stages as well as two special hidden stages. In Caravan, players can choose from any of the stages that were previously unlocked in Arcade mode and compete for a high score. Boss Attacks has two modes: Solo and Rush. In Solo, players can face-off against a single boss. In Rush, players can battle one after another until all the bosses are defeated.

Every Extend Extra Extreme comes in four main modes: 'E4: The Game Unlimited', 'E4: The Game Time Limited', 'S4: Wiz Ur Muzik', and 'R4: The Revenge'. E4: The Game Unlimited and E4: The Game Time Limited are the two main game modes. In "Unlimited", players can play as long as they want so long as they keep gaining lives, and extending time. In "Time Limited", players cannot extend time. In "S4: Wiz Ur Muzik" players can choose their own music stored in the Xbox 360 hard drive. In 'R4: The Revenge' players have the ability to shoot projectiles and attacking enemies directly, however the only hit that will count towards destroying the player is the green circle. Players can choose their movement speed and one of two modes of firing prior to the start of the game, "Four Way", and "Spread". Four way shoots projectiles from all points of your character, and Spread shoots projectiles from one specific point of your character. Players are tasked with destroying a set number of enemies until they encounter the "Boss Enemy". Destroying any enemy will give players slight amounts of "Level" which increases the number of projectiles that players can fire by one, to a maximum level of 20. every 25 stages, bosses 1–4 will have an extra one spawn with them, however the fifth boss has increased health instead. The final stage is 100.

Both Every Extend Extra and Every Extend Extra Extreme offer multiplayer modes. Every Extend Extra offers multiplayer via PSP's ad-hoc mode and Every Extend Extra Extreme offers online multiplayer through Xbox Live.