Silkworm (video game)

Silkworm is a horizontally scrolling shooter developed by Tecmo and first released for arcades in 1988. In 1989 it was ported to the Amiga, Atari ST, Commodore 64, ZX Spectrum, Amstrad CPC and NES (1990) systems by The Sales Curve and released by Virgin Mastertronic.

Silkworm inspired the game SWIV, while not a direct sequel, it followed the same core gameplay design of a helicopter/jeep team, albeit as a vertically scrolling shooter instead of a horizontally scrolling one and was described as "inspired by" and a spiritual successor by several reviews, both of the time and contemporary, respectively.

Release
Silkworm was released at a time where side-scrolling shooting games were among the most popular genres - it was released at the same time as Forgotten Worlds, Sanxion, Mr. Heli and DNA Warrior.

The Spectrum version took three months to develop and was converted from the Amiga version which was almost identical to the original. The game reached number three in the UK Spectrum sales charts, behind RoboCop and Dragon Ninja.

In November 1990, Virgin re-released Silkworm as part of the Edition 1 compilation, which also included Double Dragon, and the shoot'em ups Gemini Wing, and Xenon.

Gameplay
The player can take control of a jeep mounted with a machine gun or a helicopter mounted with forward and downward firing guns. Two players can work simultaneously and cooperatively against enemies, with one playing as the jeep and one as the helicopter.

Silkworm featured a variety of enemies, some of which had specific weaknesses, such as the armoured AA guns that could only be harmed when their shields were down to fire. Enemies included the "Goose" helicopter - a giant, heavily armoured "mini-boss" helicopter that was composed of several smaller vehicles connected together.

The players collect shields (which could alternatively be shot by the player in order to destroy all enemies on the screen), power cells which increase firepower and an additional bonus can be added to the score achieved. The game gets harder on the completion of each level, which feature destructible environmental elements, such as buildings and ancient ruins.

The speed was one of the defining parts of the gameplay, which the programmers who worked on the home conversions were keen to preserve, using a variety of programming techniques. Silkworm featured a background music theme composed by Barry Leitch, which went on to be included on a Sinclair User covermounted cassette, along with Shinobi and Continental Circus.

Ending
As an arcade game Silkworm has no ending, but the home conversions were altered to have either a victory screen, or a more involved final sequence. The end text reads:

AND HISTORY RECORDS THAT DURING THESE 11 DAYS MANY LIVES WERE LOST. PEACE RETURNED TO THE NOW DECIMATED COUNTRYSIDE. THE PEOPLE RETURNED TO FIND CROPS RUINED, CHURCHES DEFILED AND THE VILLAGE POND DRIED UP. A MEETING OF THE ELDER'S PLEASANT PEASANTS IN THE LOCAL PUB DISCOVERED THAT THE PEOPLE SAW THE FUNNY SIDE OF IT.

Reception
In Japan, Game Machine listed Silkworm on their April 1, 1988 issue as being the fifth most popular table arcade unit at the time.

The game was well received. Your Sinclair praised the 2-player mode and the sound effects.

Legacy
The game SWIV was considered a spiritual successor to Silkworm, which The Sales Curve had previously converted to home computer formats in 1989. The game's heritage is evident from the game design whereby one player pilots a helicopter, and the other an armoured Jeep. SWIV is not an official sequel, as noted by ex-Sales Curve producer Dan Marchant: "SWIV wasn't really a sequel to Silkworm, but it was certainly inspired by it and several other shoot-'em-ups that we had played and loved."

SWIV was described in the game's manual as meaning both "Special Weapons Intercept Vehicles" and "Silkworm IV".