Is Defender II on Steam?

No. Defender II is not distributed on Steam, so there is no Steam Charts or SteamDB player count for it. Its live popularity is tracked here via Twitch viewership instead.

What platforms is Defender II on?

Defender II is available on Atari 2600, Arcade, IBM PC, Apple II, Commodore 64, NES, Amiga, Atari ST.

When did Defender II release?

Defender II was first released on August 1, 1984.

Defender II

Aug 1, 1984ShooterAtari 2600ArcadeIBM PCApple IICommodore 64

Defender II — frequently asked questions

Is Defender II on Steam?: No. Defender II is not distributed on Steam, so there is no Steam Charts or SteamDB player count for it. Its live popularity is tracked here via Twitch viewership instead.
What platforms is Defender II on?: Defender II is available on Atari 2600, Arcade, IBM PC, Apple II, Commodore 64, NES, Amiga, Atari ST.
When did Defender II release?: Defender II was first released on August 1, 1984.

About Defender II

Save the humanoids from the impending aliens in the sequel to Defender. The task is still rescuing humanoids before Landers can turn them into Mutants, while avoiding and shooting other foes, however you must now carry humanoids to safety through the Stargate of the title. Entering this Stargate not only warps you to the nearest humanoid in jeopardy, but can also warp you ahead (while on the first 15 levels) if you enter it with 4 or more humanoids, and give you extra lives if you warp with 10 humanoids, so there is a trade-off between guaranteeing the safety of existing humanoids, and trying to advance your position There are more enemies on screen than ever before. The Inviso button makes you invisible to enemies, but also to yourself, so you will have to follow your bullets to work out where on the screen you are.

Summary via IGDB.

Defender II on Wikipedia

Stargate is a 1981 horizontally scrolling shooter video game developed by Vid Kidz and published by Williams Electronics for arcades. Designed by Eugene Jarvis and Larry DeMar, it is a sequel to Defender, which was released earlier in the year. It was the first of only three productions by Vid Kidz, an independent development house formed by Jarvis and DeMar. Some home ports of Stargate were renamed Defender II for legal reasons.

Source: Wikipedia (text under CC BY-SA 4.0).

Game details

Platforms: Atari 2600, Arcade, IBM PC, Apple II, Commodore 64, NES, Amiga, Atari ST
Developer: Vid Kidz
Publisher: Atari
Game modes: Single player
Themes: Science fiction

Details via IGDB.

Every version compared

Prices, contemporary reception and the studio credited for each release

Platform	Year	Loose	Complete	Sealed	Built by
Atari 2600	1984	$29	$58	$52	Atari (designed by Bill Aspromonte)

Also released on: Arcade · IBM PC · Apple II · Commodore 64 · NES · Amiga · Atari ST. We haven’t priced or authenticated those versions yet.

Collector value & authenticity

Atari 2600 · PriceCharting sold data · Verified 2026-10-06

Loose

$29

Complete

$58

Sealed

$52

Label variants

Release	Loose	Complete	Sealed
Defender II	$33	$40	$55

Release record

Territory	Label	Catalog #	Rarity
North America Atari	Red	CX26120	Scarce+
North America Atari	Silver - 1985	CX26120	Scarce+

Source: Catalog numbers, label types, rarity, controllers and player counts: AtariAge 2600 software database

Region: NA
Released: 1984
Controller: Atari Joystick
Players: 1
Authenticity: Low

Not in Atari 50 — other compilations and plug-and-plays are not tracked hereLow counterfeit risk

Atari 2600 prices, all games & how to spot a fake

Atari's 2600 Stargate, sold under two titles for the same game.

Stargate was the 1981 Williams arcade sequel to Defender, designed by Eugene Jarvis and Larry DeMar at Vid Kidz. Some home ports were renamed Defender II for legal reasons, and the 2600 version exists under both names. Bill Aspromonte designed it for Atari, Inc., released in June 1984. Little is documented specifically about the 2600 version.

How it was made

Cartridge & preservation record

Program size 8 KB, measured from the preserved dump.

Catalogue number as recorded for the physical release.

How the Atari 2600 version differs

The 2600 cartridge was first sold as Stargate and renamed Defender II for a later re-release, because Williams wanted to secure the Defender trademark.

Also on other platforms

Arcade · IBM PC · Apple II · Commodore 64 · NES · Amiga · Atari ST

Atari 2600	Atari (designed by Bill Aspromonte)
NES	HAL Laboratory
Amiga	Jeff Minter

NES. HAL Laboratory's NES port, released in the US as Defender II, shares its title jingle with HAL's Millipede and Joust ports and reuses music from Mike Tyson's Punch-Out!!.
Atari 5200. Atari programmer Steve Baker was developing 5200 and Atari 8-bit ports in 1984, but neither was released.
Amiga. The Amiga and Atari ST versions, by Jeff Minter, bundle Defender, Stargate and Defender II together.

Before you buy

Check which label you are looking at. Stargate and Defender II are the same 2600 game under two titles, and they sell for similar money, so buy whichever label you prefer. No fakes are documented. Check the label edges and ask for a working test.