Infinity Blade

In the primary portion of Infinity Blade, the player character travels a mostly linear path through a ruined castle and fights one-on-one battles with oversized enemies. The path through the castle is a series of discrete locations where the player can pan the camera around the stationary player character to view a fully three-dimensional area. The player taps locations highlighted onscreen to trigger either a short cutscene as the player character moves to the next location, or a sword battle with an enemy. During combat, the player controls the character's sword by swiping a finger across the screen.

Players can touch icons at the bottom of the screen to dodge attacks by ducking right or left, or to block attacks with a shield, which has a limited number of uses during a single battle. Players may also parry incoming attacks with an intercepting sword move that, for example, parries an attack from the left with a swipe to the left. Each of these three counters can leave the enemy vulnerable to counterattack for a short period, but incorrect counters result in damage to the player character, as reflected in the health bar. When players fail in battle en route to the God King, the game resets to the location preceding the previous battle.

Infinity Blade was created by Chair Entertainment, a subsidiary company of Epic Games. In July 2010, Chair had both recently finished the Xbox Live Arcade game Shadow Complex and been acquired by Epic. Chair was brainstorming Kinect and Wii games, including an idea similar to Infinity Blade, and Epic was nearing completion of an iOS version of the Unreal Engine 3 graphics engine and in need of a "killer game" to show it off. Epic had previously licensed the engine for use in numerous console and personal computer games.

They asked Chair to develop a game for the engine in five months, with a playable demo for the Apple Special Event conference in two months. The team decided within a few days to work on the Infinity Blade concept, codenamed "Project Sword". Instead of normal initial game development, where working prototypes test gameplay ideas, Chair spent the first week of development refining the gameplay concept on paper before beginning to code. Many of the core gameplay ideas were developed in their first few hours.

Infinity Blade was noted for its sales at launch, selling more than 270,000 copies and making over US$1.6 million in its first four days—the "fastest-grossing app" ever released for iOS at the time. By the end of 2011, it had made at least US$23 million in revenue. Around fourteen months after the initial release, Chair noted that half of the game's sales were for the iPhone and half were for the iPad and iPod. After releasing the sequel, Epic Games noted in 2012 that the series was Epic's most profitable by measure of revenue against person-hours spent in development.

Infinity Blade was reviewed by several major gaming sites in addition to mobile game-focused sites. Critics praised the game's graphics heavily. IGN reviewer Hilary Goldstein said that it was "an absolute stunner for any handheld device and ushers in a new era of possibility for high-end graphics." GamePro's Ryan Rigney called the game "downright gorgeous" and said that the graphics were almost at the level of an Xbox 360 game, which was echoed by John Meyer of Wired, who claimed that it had the best graphics of any iPad game. The reviewer for Edge further praised the art direction, especially with regards to the enemy and armor designs.