The player controls a space ship fitted with different weapons (front and back, linked to the same button, and up to two external pods with their own buttons) and other equipment. The game presents a variety of enemies (some flying, some fixed, some on rails) and bosses, with many occurrences of fixed and/or indestructible obstacles. Before the player's starship is destroyed it must take enough damage to exhaust several points of shields (which regenerate over time) and armor.
Tyrian's full game mode features a credit and equipment-buying system, and the shield/armor hit points which are similar to game mechanics in Raptor: Call of the Shadows, another PC game from the same period. The arcade mode has characteristics from coin-op arcade shooters, such as in-game powerups and extra lives.
Difficulty
There are three levels of difficulty to choose from: Easy, Medium, and Hard, as well as the hidden options of Impossible, Suicide, and Lord of the Game. Hard difficulty and above employ enemies with more health as well as fire more bullets per second. Certain hidden levels are only available at hard difficulty, which provide ample opportunities for unique powerups and upgrades. In certain levels, the Hard setting also prevents the player from seeing enemies outside a conical line-of-sight. Upon completion of the game, the player receives a password for one of the several hidden ships, as well as the options for replaying the game at a higher difficulty setting.
Full story mode
The main mode is the single player full story mode. This mode includes storyline-related messages in the shop at the start of the level and when certain enemies are destroyed. At certain points in the game, the player has a choice of levels.
The player begins with one standard weapon, which may be upgraded or replaced. Later weapons include multi-directional cannons, lightning guns, beam lasers, heavy missiles, and homing bombs. The player's craft accommodates a front and a rear gun; where front weapons are mostly limited to forward arcs, "rear" weapons often come with wider coverage including side and rear shots. Some rear weapons have two selectable fire modes, focusing either mostly forward or mostly sideways/rearward. Both types of weapons have eleven levels, making them upgradeable 10 times, although higher levels cost exponentially more, as well as require a stronger generator to support them..
The player can purchase up to two "sidekicks" which fly alongside the ship. Some simply act as another weapon, others have stronger attacks but are limited by a limited ammunition pool. Other upgrades include increased shields, more powerful generators to allow for stronger weapons and shields, more armour, and higher maneuverability.
Shops let the player build a strong ship on a budget with no penalty for failing and trying a different build. Any weapon can be upgraded in stores, even if not available for sale, and any item can be sold. However, the player cannot obtain sold items again without reaching another level which offers them. In many cases a single secret level in the whole game may contain a unique weapon or equipment.
Arcade mode
In arcade mode, the player picks up the front guns, rear guns, and sidekicks along the way, instead of purchasing them. Front weapons are upgraded by picking up purple bubbles from destroyed enemies. The number of purple orbs required increases exponentially to advance to higher power levels. Front and rear guns can also be upgraded to the next level by picking up powerup pods, which are found by destroying a specific enemy. The ship, shields, and generators are not upgradeable, although the player is given a medium attribute ship.
It is possible to switch between the single player and (1 person) arcade modes using a secret routine (not cheat codes). Since it is possible to find exotic weapons early in arcade mode; using this switch allows such weapons to be brought over to single player. Likewise, generator and shield upgrades from single player will result in a better ship for arcade mode.
Two player
In the two player (arcade mode only), the players control two different ships, known as the "Dragonhead" and "Dragonwing". Both players can combine their ships into one, forming the "Steel Dragon", with the first player controlling the combined ship, and the second player controlling a turret. Tyrian enables the two players to be connected via modem.
The Dragonhead has front gun powerups (with more variety than the Dragonwing's rear gun pickups), has better maneuverability, and a smaller profile making it easier to dodge enemy fire. It also controls the "special" powerup weapons such as the Soul of Zinglon or Repulsor.
The Dragonwing is larger and slower but more heavily armored. It picks up the rear up powerups (although unlike the equivalent single player rear gun, the Dragonwing fires it mostly forward instead of the side or rear), and also controls the sidekick weapons. The Dragonwing has a unique "charge-up" ability for its main gun, where if the player decides not to fire for a short period of time, the power of their blast accumulates. There are five charge levels for each weapon, and collecting the spherical purple powerups gives the Dragonwing the ability to charge-up faster.
