Question: On what day did the publisher of Yoshi's Story unveil the new systems?

full_context: Document 1: Nintendo Entertainment System: As the 1990s dawned, gamers predicted that competition from technologically superior systems such as the 16-bit Sega Mega Drive/Genesis would mean the immediate end of the NES’s dominance. Instead, during the first year of Nintendo's successor console the Super Famicom (named Super Nintendo Entertainment System outside Japan), the Famicom remained the second highest-selling video game console in Japan, outselling the newer and more powerful NEC PC Engine and Sega Mega Drive by a wide margin. The console remained popular in Japan and North America until late 1993, when the demand for new NES software abruptly plummeted. The final Famicom game released in Japan is Takahashi Meijin no Bōken Jima IV (Adventure Island IV), while in North America, Wario's Woods is the final licensed game. In the wake of ever decreasing sales and the lack of new software titles, Nintendo of America officially discontinued the NES by 1995. However, Nintendo kept producing new Famicom units in Japan until September 25, 2003, and continued to repair Famicom consoles until October 31, 2007, attributing the discontinuation of support to insufficient supplies of parts.
Document 2: Donkey Kong Country Returns: Donkey Kong Country Returns is a side - scrolling platformer video game developed by Retro Studios and published by Nintendo for the Wii console. The game was released first in North America in November 2010, and in PAL regions and Japan the following month. A stereoscopic port of the game, titled Donkey Kong Country Returns 3D, was released for the Nintendo 3DS in May 2013, and in Japan the following month.
Document 3: Yoshi's Story: Yoshi's Story is a side-scrolling platform game published and developed by Nintendo for the Nintendo 64. It was first released in Japan in December 1997, and worldwide the following year. It was re-released on the Wii's Virtual Console service in 2007, and later for the Wii U's Virtual Console in 2016.
Document 4: Nintendo Entertainment System: For its complete North American release, the Nintendo Entertainment System was progressively released over the ensuing years in four different bundles: the Deluxe Set, the Control Deck, the Action Set and the Power Set. The Deluxe Set, retailing at US$199.99 (equivalent to $475 in 2016), included R.O.B., a light gun called the NES Zapper, two controllers, and two Game Paks: Gyromite, and Duck Hunt. The Basic Set, retailing at US$89.99 with no game, and US$99.99 bundled with "Super Mario Bros." The Action Set, retailing in 1988 for US$149.99, came with the Control Deck, two game controllers, an NES Zapper, and a dual Game Pak containing both Super Mario Bros. and Duck Hunt. In 1989, the Power Set included the console, two game controllers, a NES Zapper, a Power Pad, and a triple Game Pak containing Super Mario Bros, Duck Hunt, and World Class Track Meet. In 1990, a Sports Set bundle was released, including the console, an NES Satellite infrared wireless multitap adapter, four game controllers, and a dual Game Pak containing Super Spike V'Ball and Nintendo World Cup. Two more bundle packages were later released using the original model NES console. The Challenge Set of 1992 included the console, two controllers, and a Super Mario Bros. 3 Game Pak for a retail price of US$89.99. The Basic Set, first released in 1987, was repackaged for a retail US$89.99. It included only the console and two controllers, and no longer was bundled with a cartridge. Instead, it contained a book called the Official Nintendo Player's Guide, which contained detailed information for every NES game made up to that point.
Document 5: Super Mario World: Super Mario World is a side - scrolling platform game in which the player controls Mario, the on - screen protagonist. The game shares similar gameplay mechanics with earlier titles in the series -- Super Mario Bros., Super Mario Bros. 2, and Super Mario Bros. 3 -- but introduces several new elements. As well as the running and jumping moves found in past games, the player can float with the aid of special items, and execute new types of jumps such as the spin jump. The game has 96 levels.
Document 6: Yoshi Touch & Go: Yoshi Touch & Go, known in Japan as , is a video game that was developed and published by Nintendo for the Nintendo DS. It debuted in Japan on January 27, 2005, in North America on March 14, 2005, and in Europe on May 6, 2005. As of August 2007, the game sold 197,337 copies in Japan. "Yoshi Touch & Go" was produced by Takashi Tezuka and directed by Hiroyuki Kimura. It was one of the launch titles for the DS in Japan. The game was released on the Wii U Virtual Console in 2015.
Document 7: Nintendo Entertainment System: Several companies, refusing to pay the licensing fee or having been rejected by Nintendo, found ways to circumvent the console's authentication system. Most of these companies created circuits that used a voltage spike to temporarily disable the 10NES chip in the NES. A few unlicensed games released in Europe and Australia came in the form of a dongle that would be connected to a licensed game, in order to use the licensed game's 10NES chip for authentication. In order to combat unlicensed games, Nintendo of America threatened retailers who sold them with losing their supply of licensed titles. In addition, multiple revisions were made to the NES PCBs to prevent these games from working.
Document 8: Super Mario Land: Super Mario Land is a 1989 side-scrolling platform video game developed and published by Nintendo as a launch title for their Game Boy handheld game console. It is the first "Mario" platform game ever to be released for a handheld console. In gameplay similar to that of the 1985 "Super Mario Bros.", but resized for the smaller device's screen, the player advances Mario to the end of 12 levels by moving to the right and jumping across platforms to avoid enemies and pitfalls. Unlike other "Mario" games, "Super Mario Land" is set in Sarasaland, a new environment depicted in line art, and Mario pursues Princess Daisy (who makes her debut in this game). The game also includes two "Gradius"-style shooter levels.
Document 9: Nintendo Entertainment System: The Nintendo Entertainment System (commonly abbreviated as NES) is an 8 - bit home video game console that was developed and manufactured by Nintendo. It was initially released in Japan as the Family Computer (Japanese: ファミリーコンピュータ, Hepburn: Famirī Konpyūta) (also known by the portmanteau abbreviation Famicom (ファミコン, Famikon) and abbreviated as FC) on July 15, 1983, and was later released in North America during 1985, in Europe during 1986 and 1987, and Australia in 1987. In South Korea, it was known as the Hyundai Comboy (현대컴보이 Hyeondae Keomboi) and was distributed by SK Hynix which then was known as Hyundai Electronics. The best - selling gaming console of its time, the NES helped revitalize the US video game industry following the video game crash of 1983. With the NES, Nintendo introduced a now - standard business model of licensing third - party developers, authorizing them to produce and distribute titles for Nintendo's platform. It was succeeded by the Super Nintendo Entertainment System.
Document 10: Nintendo Entertainment System: Video output connections varied from one model of the console to the next. The original HVC-001 model of the Family Computer featured only radio frequency (RF) modulator output. When the console was released in North America and Europe, support for composite video through RCA connectors was added in addition to the RF modulator. The HVC-101 model of the Famicom dropped the RF modulator entirely and adopted composite video output via a proprietary 12-pin "multi-out" connector first introduced for the Super Famicom/Super Nintendo Entertainment System. Conversely, the North American re-released NES-101 model most closely resembled the original HVC-001 model Famicom, in that it featured RF modulator output only. Finally, the PlayChoice-10 utilized an inverted RGB video output.
Document 11: List of Super Nintendo Entertainment System games: Of the console's 783 official releases, 249 were exclusive to North America and 62 to Europe. The Super NES was released in North America on August 23, 1991 with its launch titles being Super Mario World, F - Zero, Pilotwings, SimCity, and Gradius III. The last game to be officially published for the system was Frogger in 1998. The best - selling game is Super Mario World with over 20.6 million units sold. Despite the console's relatively late start, and the fierce competition it faced in North America and Europe from Sega's Genesis / Mega Drive console, it was the best - selling console of its era.
Document 12: Super Nintendo Entertainment System: In October 1997, Nintendo released a redesigned model of the SNES (the SNS-101 model) in North America for US$99, which sometimes included the pack-in game Super Mario World 2: Yoshi's Island. Like the earlier redesign of the NES (the NES-101 model), the new model was slimmer and lighter than its predecessor, but it lacked S-Video and RGB output, and it was among the last major SNES-related releases in the region. A similarly redesigned Super Famicom Jr. was released in Japan at around the same time.
Document 13: Nintendo Entertainment System: In the UK, Italy and Australia which share the PAL A region, two versions of the NES were released; the "Mattel Version" and "NES Version". When the NES was first released in those countries, it was distributed by Mattel and Nintendo decided to use a lockout chip specific to those countries, different from the chip used in other European countries. When Nintendo took over European distribution in 1990, they produced consoles that were then labelled "NES Version"; therefore, the only differences between the two are the text on the front flap and texture on the top/bottom of the casing.
Document 14: Nintendo Entertainment System: At June 1985's Consumer Electronics Show (CES), Nintendo unveiled the American version of its Famicom. This is the system which would eventually be officially deployed as the Nintendo Entertainment System, or the colloquial "NES". Nintendo seeded these first systems to limited American test markets starting in New York City on October 18, 1985, following up with a full-fledged North American release of the console in February of the following year. Nintendo released 17 launch titles: 10-Yard Fight, Baseball, Clu Clu Land, Duck Hunt, Excitebike, Golf, Gyromite, Hogan’s Alley, Ice Climber, Kung Fu, Pinball, Soccer, Stack-Up, Tennis, Wild Gunman, Wrecking Crew, and Super Mario Bros.h[›] Some varieties of these launch games contained Famicom chips with an adapter inside the cartridge so they would play on North American consoles, which is why the title screen of Gyromite has the Famicom title "Robot Gyro" and the title screen of Stack-Up has the Famicom title "Robot Block".
Document 15: Mario Bros.: Mario Bros. is a platform game published and developed for arcades by Nintendo in 1983. It was created by Shigeru Miyamoto. It has been featured as a minigame in all of the Super Mario Advance series and numerous other games. Mario Bros. has been re-released for the Wii's, Nintendo 3DS's, and Wii U's Virtual Console services in Japan, North America, Europe and Australia. It has also been re-released through Nintendo Switch Online.
ground_truth: October 18, 1985
sub_queries: Who published Yoshi's Story? Answer: Nintendo
What day did Nintendo unveil the new systems? Answer: October 18, 1985