Danmaku Unlimited 2



Danmaku Unlimited 2 is a vertical-scrolling shooter developed and published by Doragon Entertainment on iOS, Android and Steam.

Controls
default keyboard controls:


 * Z (Hold): Fires the ship's main shot and option shots
 * X (Release): Burst laser (Burst mode only)
 * X (Hold): Focus mode
 * Z+X (Hold): Focus Shot (Classic mode only)
 * C (Press): Trance

Styles

 * Burst Mode
 * Classic Mode

Ship Upgrades
The game features an upgrade system which allows players to add and boost three offensive and/or three defensive properties.


 * Offensive Upgrades: Upgrading offense adds additional permanent units to the player ship which shoot additional projectiles. The range of offensive upgrades is 0 to 3. The required amount of points decreases per level (400-300-200). Maxing out one offensive upgrade requires 900 points.
 * Focus: (WIP)
 * Track: (WIP)
 * Wide: (WIP)
 * Defensive Upgrades: Upgrading defense allows the player ship to take more hits before the game is over. The range of defensive upgrades is 1 to 5. The required amount of points increases per level (100-150-200-250). Maxing out one defensive upgrade requires 700 points.
 * A.D.S: The A.D.S determines the amount of times the player ship can get hit without being destroyed. The A.D.S gauge is displayed on the left side of the screen and it can not be recharged.
 * Lives: The lives upgrade determines the amount of extra ships the player has.
 * Continue: Determines the amount of times the player can continue before the game is over. Using a continue will set the A.D.S and lives to the amount chosen in the upgrade menu.

The amount of upgrade points available depends on the current upgrade rank which is raised over multiple runs.

Weapons

 * Trance
 * Burst

Items

 * Orbs: Orbs charge the Burst laser and can not be obtained in Classic mode. The estimated amount of orbs required to reach the minimum threshold for a laser is ~40. The estimated amount of orbs required to fully charge the Burst gauge is ~160.
 * Orbs are generated by destroying enemies and point blanking stronger enemies. Major enemies, mid boss and bosses will cancel their bullets into orbs if they're destroyed while neither Burst nor Trance are active.


 * Multiplier Crystals: Increase the stage multiplier value (the exact value added to the multiplier has yet to be determined, it should be somewhere between 0.05 and 0.10 in Burst mode and appears to be higher than that in Classic mode).
 * In Burst mode, crystals are generated by cancelling bullets with the burst laser. Additionally, destroying an enemy with the burst will cause all of their bullets to turn into crystals as well. During Trance most regular enemies will also turn their bullets into crystals upon being destroyed. However, there is one exception: Enemies which cancel their bullets without turning them into items upon being destroyed without a laser or Trance will turn their bullets into Golden stars upon being destroyed with a laser in Trance.
 * In Classic mode, crystals are generated by point blanking enemies and initiating Trance.


 * Blue Stars: (WIP)


 * Golden Stars: (WIP)

Scoring
Scoring in Danmaku Unlimited 2 is exponential. The goal is to continuously build up the scoring factors from the start to the end of the run and prevent them from getting reset by getting hit or losing a ship for as far into the run as possible. This section will list all scoring factors and conclude with how to cash in on score efficiently.

Scoring factors

 * Stage Multiplier: The stage multiplier multiplies any points obtained. After clearing a stage its value does not get carried over to the next stage. Instead, a fraction of its value will be added to the Trance multiplier (Easy: 1/20, Normal: 3/40, Hard: 1/8, Extreme: 1/4). The base value is increased by collecting Multiplier Crystals. In Burst mode the multiplier will be multiplied by 4 during Trance. Getting hit while Trance is not active will half the stage multiplier. Losing a ship will reset its base value to 1.


 * Graze: The graze counter gets increased by 1 with every projectile grazed by the ship. However, once the ship gets hit the graze counter will be reset to 0.


 * Trance Multiplier: The Trance multiplier multiplies the point value during Trance. Its value gets increased at the end of every stage by a fraction of the end stage multiplier. Losing a ship will reset its value to 1.


 * Points: Points is a factor used for scoring which results out of the graze counter and the Trance multiplier. Its base value is Graze*16. During Trance the value will be multiplied by the Trance Multiplier. It caps at 9,999,999pts.

Methods of scoring

 * Destroying enemies: Apart from the stage multiplier and the points value, two additional factors determine the amount of score obtained by destroying enemies:
 * Enemy value: [needs more research]
 * Proximity Multiplier: The proximity multiplier multiplies the score obtained by an enemy. This multiplier is bigger based on how close the player ship is. Its highest value is 16. If the player ship is too far away, its value is 1 and doesn't get displayed.
 * The ascertained formula for score obtained by destroying an enemy is: (enemy value + points value) * proximity multiplier * stage multiplier. Since the stage multiplier has more decimal places than displayed, calculations based on the displayed factors are likely to be slightly off.


 * Damaging enemies: [needs more research]


 * Collecting stars: [needs more research]


 * Flawless Phase Bonus: [needs more research]


 * Stage Clear Bonus: [needs more research]

Video References

 * Full runs: Danmaku Unlimited 2/Video Index

Bugs

 * Score inaccuracy: Every time points are meant to get added to the score, the calculation itself is done with floating point values only (IEEE 754). As a result, score will become increasingly inaccurate the higher it is as the result of the addition gets rounded to the nearest representable value. If score is very high and the amount of points to be added too low, the score may not change at all.
 * Stage bonus : Occasionally, the stage end bonus may not be applied to the score. However, if said score + the displayed stage bonus exceeds the high score, the high score will be updated to that value regardless.
 * High score saving : The game either reads or writes a high score improperly if its value exceeds 4,294,967,295 (2^32-1) as it only handles four bytes.