Praised for its then-advanced graphics and sound, the game was generally well-received on the PC, though the critical response was less positive for the Dreamcast version. A sequel entitled Incoming Forces was released in 2003 exclusively for the PC. An arcade version of the game, utilising a unique hardware interface, was released in the same year.
There are three different game modes. The Campaign mode follows the main storyline in which the player must complete a series of objectives to neutralise the alien threat. Typical goals include transporting cargo and defending allied convoys. Two variants of the campaign exist: Campaign Action purely consists of the simulation missions; Campaign Tactics features the same main missions as Campaign Action, but with some extra sub-missions. These sub-missions take place in the "Tactical display", where the player controls several vehicles and gun emplacements in a similar manner to real-time strategy games.
Either campaign consists of ten missions (referred to as "phases" in the game) in each of the six locations. These locations can also be accessed in the Arcade mode. This mode sees the player fight off alien craft while picking up as many "power-ups" (items which confer some advantage upon the player, such as temporary invulnerability and upgraded weaponry) as is possible. The same mechanics apply to the multiplayer mode, with some slight variations depending on the game type selected. Multiplayer is available in split-screen mode on both platforms in addition to networking and Internet options on the PC version.
The game is set in six locations: Kenya, defending the ADATA facility; the Arctic, attacking an alien base while defending a human one; the North Atlantic Ocean, where the player must defend oil rigs and attack a second alien base; California, where parts of a fleet to invade the alien's moon base must be defended; the Moon, attacking a further alien base; and a planet in the Crab Nebula, assaulting the planet from which the alien attackers came.
If the player has completed these in the Campaign Action mode, then in addition to these ten missions in each location, there are bonus "virus" scenarios, with one level in each location. Shortly before these missions, the aliens launched four virus bombs which impacted in the four location on Earth the player had previously visited. All buildings in these areas must be destroyed by the player to prevent the virus from spreading further.
The PC version of Incoming was generally well-received, with a GameSpot review aggregate score of 8.2/10. British magazine PC Zone gave the game a glowing score of 90%, describing it as "bloody good," with "some modest simulation elements." PC Zone praised the setting of the game: "a refreshing change from the deep space of most futuristic combat sims, and something which definitely has a positive effect on gameplay." The review concluded by saying that "it's as fun as it looks. Just for once, all those people who don't read reviews and buy games purely on the strength of pretty pictures on the packaging are gonna find themselves playing a very, very enjoyable game."
Though considering the game "pretty darn tough," IGN praised the game's variety and length. It also praised the sound and graphics, though the latter was a source of criticism: "Incoming's got it all... but it all comes at a high price: getting this game to run on our PCs was one big pain in the butt." Despite calling it "an outstanding-looking and great playing game," IGN only gave the game a "decent" 7.0/10 because of the system problems. Conversely, GameSpot's review noted none of these hardware issues, praising the visuals as "some of the finest... of any action game". The reviewer, however, described the game design as "strong yet slightly flawed... [it] definitely pulls you in, but leaves a little to be desired as far as keeping you there," complaining that "what [the developer] have presented gets tiresome quickly." Rating the game 7.8/10, GameSpot summarised the game as "a fine game and a definite must-have for arcade fans... What it lacks is a realization that computer games have moved beyond this simplistic style of gameplay".
The Dreamcast port of Incoming received a mixed reaction from critics, with a Game Rankings average score of 63%. IGN opened their review by saying that "although the game is lacking in many areas, there's more than enough here for the hardcore shooting fans out there to have their requisite blast of shooting action." Though criticizing the graphics' ability to "get in the way at times," the "very vague" mission briefings and the "odd flying model for the planes," the reviewer conceded that "if you're a hardcore shooting fan, and you're looking for a good challenge, you'll probably want to look into Incoming." The game was given as score of 7.0/10. GameSpy's review was harsher, describing the plot as "the same recycled garbage used in tons of other games of this type," the multiplayer split screen mode as "lame" and the objectives as "mundane." The reviewer also noted graphical issues, clipping problems and poor controls. Though dismissing the graphics as "a bit dated," the reviewer did acknowledge the "nifty special effects." Giving the game a score of 6/10, it was admitted that "Incoming may be worth a rental... [it] is only slightly better than mediocre."
In a rare positive review for the Dreamcast version, GameVortex rated the game 9/10. The reviewer described the visuals as "some of the most breathtaking visuals you'll find in any game." Though describing the multiplayer as "fun", it considered "by far, the best [mode to be] Campaign mode." The review concluded by describing the game as "lots of fun and highly recommended."