known in North America as Lightening Force: Quest for the Darkstar, is a shoot 'em up video game developed and published by Technosoft for the Mega Drive in 1992. It is the fourth installment in Technosoft's Thunder Force series, and the third and final one created for the Mega Drive. It was developed by the team at Technosoft that ported Devil's Crush to the Mega Drive rather than the team that developed the previous Thunder Force games. Like its predecessors, it is a horizontally scrolling shooter, but it also features extensive vertical scrolling with large playing fields. The game was considered by journalists as one of the best shooters on the Mega Drive when it was launched. Critics especially praised the game's graphics, including the vertical and parallax scrolling for illustrating the immense environments. Some believed that underneath the graphical sheen, the gameplay was relatively average however. Thunder Force IV was rereleased on the Sega Saturn in 1996 and the Nintendo Switch in 2018. Gameplay Thunder Force IV is a horizontal shoot 'em up. The story takes place two years after the events of Thunder Force III. The player takes on the role of a fighter pilot to battle the Orn Empire, which is plotting the extinction of the human race. The first four stages can be selected in any order. There are ten stages total. They scroll horizontally automatically, and the player can also explore up and down to scroll the screen vertically and reveal a larger playing field. The player can change the speed of their ship at any time for easier maneuverability. Scrolling up and down will reveal different waves of enemies the player can shoot down, as well as hidden power-ups. At the end of each stage is a boss, and sometimes there are bosses mid-stage. Some enemies will drop power-ups that if picked up by the player will arm the ship with new weaponry, including a variety of missiles and lasers that fire in different patterns. Each weapon has advantages and drawbacks, and is more or less effective depending on the battle situation the player finds themselves in. The player can hold multiple weapons and cycle through them at will. Other power-ups include shields and satellite ships that revolve around their ship and multiply their firepower. Half-way through the game, the player gains a powerful "Thunder Sword" attack which deals massive damage to enemies. It