Fish Target: Each level has a fish target requirement, shown in the bottom left corner of the screen. Destroy fish by firing upon them with your various ammo types. Fulfil your fish target to beat the level!
Oxygen: Oxygen slowly depletes over time or if Viktor takes damage. A Game Over will occur if the oxygen meter is emptied. The remaining oxygen is shown by the Oxygen Meter to the right of the Fish Target display.
Shooting: Tap the screen to fire the currently selected ammo towards the tapped location. Tap and hold the screen to repeatedly fire in that direction.
Ammo Types: Tap the ammo ability underneath Viktor to change ammo. Most types of ammo have a limited number of uses each level. Each ammo type has different effects:
Normal Shot: A basic ammunition type. It deals low damage but fires rapidly and has no ammo limit.
Torpedo: A powerful weapon that deals high damage to the first object it hits.
Bomb: Explodes on contact, dealing moderate damage in a large area.
Laser: A laser that pierces all targets in its way, dealing high damage to all targets hit.
Lure: Places a lure at the selected location. For a limited time, fish will be drawn to the lure and will not move away.
Shield: Viktor is protected from taking damage by a shield. The shield will absorb a single hit before depleting but will regenerate over time.
Power Gems have a chance to be collected whenever a fish is destroyed.
Oxygen Refill: Collecting an Oxygen Refill Gem replenishes some of your Oxygen Meter, up to its maximum starting amount.
Ammunition Refill: Collecting an Ammunition Refill Gem will instantly give 1 extra ammo for torpedos, bombs or laser, chosen randomly.
Exploding Fish: Collecting an Exploding Fish Gem causes all fish to combust when fired upon and deal damage to surrounding fish. This effect persists for a limited time, shown by the power meter.
Double Damage: Collecting a Double Damage Gem will cause all ammo types to deal double damage to any targets fired upon. This effect persists for a limited time, shown by the power meter.
Slow Time: Collecting a Slow Time Gem will slow down all the fish. This effect persists for a limited time, shown by the power meter.
Infinite Ammo: This ability is unlocked by equipping an Infinite Ammo Ultra Booster Card before starting the game. It provides unlimited ammo across all weapons for a limited time, shown by the Ultra meter. Activate via the Ultra meter button in the top left of the game.
Normal Fish: Shoot these fish to reach the fish target and clear the level. Larger and tougher fish take more damage to destroy but are worth more points and have a higher chance to reward Power-Gems.
Puffer Fish: Firing upon a Puffer Fish will deal damage to Viktor, decreasing the oxygen meter.
Naval Mines: These Naval Mines slowly move towards Viktor and deal damage on contact with him, decreasing the oxygen meter. They can be safely destroyed by firing upon them before they reach victor.
Leviathan Tentacles (Boss level): In the final level of the game the leviathan will appear. Fire at the Leviathan tentacles to destroy them. They will attack Viktor and decrease the oxygen meter at regular intervals if they are not destroyed.
Leviathan Spawn (boss level): On boss Levels watch out for Leviathan spawn that swim towards Viktor with deadly intent. They will deal damage on contact with him, decreasing the oxygen meter. They can be destroyed by firing upon them before they reach Viktor.
Fish Destroyed: Total points gained for defeating fish. Tougher fish are worth more points.
Mines Destroyed: Total points gained for defeating Naval Mines.
End Game Bonus: At the end of the game, leftover oxygen will convert into points.