Source: Wikipedia, "Mercs", available under the CC-BY-SA License.
Mercs (戦場の狼Ⅱ, Senjō no Ōkami Tsū, "Wolf of the Battlefield II") is a 1990 top-down run and gun arcade game developed and published by Capcom for the arcades.
The arcade version of the game had up to three players available for play. The players are members of a covert mercenary team known as the "Wolf Force". The team is composed of Joseph Gibson (Player 1 in blue), Howard Powell (Player 2 in red), and Thomas Clarke (Player 3 in yellow). Their objective is to rescue the former President from rebels in the fictional African country of Zutula, which bears resemblance to the apartheid regime in South Africa. The game has six levels, plus the final level where the objective is to rescue the president from the Hercules Transport.
The controls consist of an eight-directional joystick and two buttons: a Normal Attack and the Megacrush Attack. The player character has a vitality gauge which will gradually deplete as they take damage from enemies, however First-Aid Kits can be pick up that will restore part of the player's energy, as well as power-ups that increases their maximum vitality. The player can upgrade their default gun into an Assault Rifle, a Shotgun, a Grenade Launcher, or a Flamethrower. The Megacrush button will detonate a bomb that kills all on-screen enemies. However, the Megacrush Attack has limited uses which the player can only replenish by picking more Megacrush bombs. In certain stages, the player can pilot enemy vehicles.