Underwurlde

Underwurlde is a platform game viewed from a side-angle perspective. The player controls Sabreman, a pith-helmeted adventurer, as he jumps between platforms in a castle and its caverns to find a way to escape past the exit guardians. Sabreman must use a specific weapon—knife, catapult, and torch—that corresponds to each guardian. The player uses the keyboard's QWERTY keys to progress through a series of flip screens in which the player's character reaches the boundary of the viewable area on the screen to flip to another area, with 597 screens in all.

While Sabreman begins in a castle adorned with clocks, birds, and baskets, the character must also descend into caverns through several successive vertical screens. Sabreman automatically attaches a rope to the ceiling when the player guides him off of a ledge. The player can then swing Sabreman side to side to jump to another ledge. At the bottom of a cavern, Sabreman can ride a bubble to the top.

There is little information about the development processes of Ultimate Play the Game, which was known for its avoidance of media spotlight. Its founders, brothers Tim and Chris Stamper, were infamously taciturn both to preserve their time and to let their games speak for themselves. However, as the Sabreman series became popular, their silence contributed to the series' mystique. The main criticism of Underwurlde's predecessor and the first game in the Sabreman series, Sabre Wulf, was its similarity to an earlier game by the Stamper brothers, as both were depicted in a top-down view as action-adventure games, while Retro Gamer said that Underwurlde resolved this criticism by instead using a side view as a platform game.

The Stamper brothers claimed to have finished their third Sabreman title, the epochal Knight Lore, in advance of both of its predecessors, although more recent analysis of the code used in the games has suggested this may have been an exaggeration as the routines found in Knight Lore are far more optimised. The Stampers primarily developed for the ZX Spectrum home computer and outsourced the work of converting their games to work on other types of computers to external developers more familiar with the hardware architecture of different platforms. For instance, Firebird released the Commodore 64 versions of Sabre Wulf and Underwurlde. The game was released shortly before Knight Lore for the ZX Spectrum near the 1984 holiday season, and the Commodore 64 version was released a year later.

Reviewers recommended the original ZX Spectrum Underwurlde release. Critics noted the game world's size and appreciated the parts where Sabreman travelled by bubble. Retro Gamer described the game's near 600 flip screens as "colossal". At the time of its release, Computer and Video Games stated it was likely the most expansive world on the platform.

Later reviews noted the exceptional difficulty. Crash magazine recommended the game as "A Crash Smash".

In the early 1990s, Your Sinclair rated the game within the top fifth of their top 100 ZX Spectrum games. Stuart Campbell wrote that Underwurlde was the most simultaneously loved and hated game of its era. Though Sabreman's invulnerability to direct damage was novel, Campbell also recalled the "stratospheric level of frustration". However, the magazine's readers ranked the game near the bottom of their top 100 games for the platform.

Underwurlde was later included in the 2015 Xbox One retrospective compilation Rare Replay, wherein critics rated it among the worst of the 30 titles by Ultimate Play the Game and its successor, Rare. Kyle Hilliard (Game Informer) wrote that Ultimate's early games, such as Underwurlde, fared the worst in the package, though he was glad they were included. "By today's standards", began New Zealand newspaper The Nelson Mail, "the likes of ... Underwurlde are so clunky and archaic that they are almost laughably impenetrable; strange relics from a bygone era that serve only to illustrate how far the industry has progressed."