Touhou 2: Story of Eastern Wonderland
Object Caps
Bullet Cap
There is a limit for how many bullets can be present on screen at one time. This number caps at 150 bullets, after which bullet sources stop producing more bullets until any on-screen bullets have gone offscreen. Whether this bullet cap is applied to all bullets or only certain bullet types (like in LLS and MS) is currently unclear. An example in the game where the bullet cap can get hit is during Mima's swirly pellet pattern during her early phases of her boss fight.
Item Cap
It is possible for enemies with item drops to not drop their items, due to an item cap. This item cap is 20 items. This also includes items that went over the top of the screen. Some examples of where the item cap can be hit is during the first and second swarm of orb-enemies in Stage 3 and on Stage 5 when a bomb is used.
Enemy Cap
Just like how there is an item cap, there is also an enemy cap. A total of 25 enemies can be on screen at a time. This only really becomes relevant during the second orb-spam section in Stage 3 where there's also a number of red, invincible wireframe orbs coming down.
Items
Item Distribution
Items dropped by enemies come in several different groups. Each group determines how and when an item is dropped. This is mostly important regarding the enemies dropping one item per 3 enemies killed. These groups are as follows:
- Every enemy drops a
Power Item guarenteed - Every enemy drops a
S-Power Item guarenteed - Every enemy drops a
Point Item guarenteed - Every third enemy drops a Power Item or a Point Item
Regarding the last group, the items are always dropped in this pattern: |
|. Where in this pattern the first item is dropped is random however. There is also a 1 in 512 chance that one of these items will be replaced with a 
Bomb Item instead, then continues cycling through the item drops like normal.
The enemies in the groups that always drop a Power Item or Point Item also cannot possibly drop a Bomb Item in it's place. Which enemies belong to what item-group will be explained in this video.
Point Item Values
As is standard for most Touhou games, the higher on the screen you collect a Point Item from, the higher the value of the item is. This value varies from 2,240 and 51,200 in SoEW, whereby the game uses the following formula once the item falls below the top 48 pixels of the screen: 28,000 - (top Y coordinate of item in screen space × 70). Additionally the collection of these items and at what value they're collected at contribute to the Skill Verdict.
Boss AI Patterns
For the most part, the way how boss patterns are being carried out is pretty straightforward. If you deplete enough health of the boss, they will go to the next phase and start producing different bullet patterns. However, Marisa and Mima are two bosses who have a bit more of a working to it and so these two bosses will be explained in detail. One thing that should be mentioned about the bosses in this game, none of the bosses with the exception of the first 4 orbs of the Five Magic Stones and Marisa have a timer.* This means these bosses can last forever if you want them to. The midbosses however have a timer because the regular enemies appear in sync with the music and stage progression.
*(NOTE: From my own testing (admittedly done by using Cheat Engine to keep the post-death invulnerability timer running), all 5 orbs of the Five Magic Stones are on timers. The final orb's timer is much longer than the others, but after the attack where it steps its lasers first to the center and then to the edges, it will loop over its final set of 4 attack patterns (curved bullet arcs, arching green bullets, random bullet spray, random lasers) a few times, and will then self-destruct if not killed. I assume you can verify this fairly easily. It shouldn't take long. Further: Mima's first 3 attack phases (the ones that end with item drops) are all on timers, with each ending after that phase's attacks have repeated several times. There is no timer for the 4th phase or the 5th and final phase. I suppose this might be somewhat harder to verify in legitimate play.)
Marisa
Marisa is the only boss in the game who does not change up her pattern of attacks at any point during the fight. To determine how she carries out her attacks, we will do so by dividing her attacks into 2 attacking states she's in. One attacking state is her producing bullet patterns while 1 or more of her orbs are still active and the other attacking state when she has no orbs active. One quick thing to note is that Marisa herself is completely invincible so long as any of her orbs are still active.
Now every attack Marisa does with her orbs, is connected by another bullet pattern she does without orbs. Essentially what this means is that if she is in the process of firing one particular pattern, she will be ready to fire off her corresponding attack if her orbs are destroyed during it. Marisa has 3 bullet patterns without her orbs being active which are not connected between her orb state and non-orb state. The following page shows what bullet pattern she fires without orbs if you destroy all orbs while she's firing a certain pattern with orbs, by numbering both corresponding patterns.
Mima
Clear Bonus
Main Game
Upon clearing Stage 1-4 you will be given a Clear Bonus that is generally determined by your performance in said stage. These are the components of the bonus along with their minimum and maximum values:
| Component (JP) | Component (EN) | Formula | Minimum | Maximum | Max (Default settings) |
|---|---|---|---|---|---|
| 難易度 | Rank (Difficulty) | Difficulty level* × 2,000 | 0 | 6,000 | 6,000 |
| ステージ | Stage | (Rank + 16) × 200 | 2,000 | 6,400 | 6,400 |
| ボム | Bombs | (2,500 - (Bombs used × 500) | 0 | 2,500 | 2,500 |
| ミス | Lives | (3,000 - (Lives lost × 1,000) | 0 | 3,000 | 3,000 |
| 靈撃初期数 | Initial Bombs | (4 - Starting bombs) × 800 | 800 | 3,200 | 800 |
| 靈夢初期数 | Initial Lives | (5 - Starting lives) × 1,000 | 0 | 4,000 | 2,000 |
| Sum | 2,800 | 25,100 | 20,700 | ||
| Total Clear Bonus | Point Items collected × Sum |
* Ranges from 0 (Easy) to 3 (Lunatic).
When playing the game with default settings the Initial Bombs and Lives value will always give a bonus of 800 and 2,000 respectively. This means the maximum value possible for such runs on Easy, Normal, Hard and Lunatic are 12,300, 16,700, 18,700 and 20,700 respectively. As for the rank, on Easy your rank holds a value between -6 and 4 and -6 to 16 on other difficulties, meaning the highest value possible on this difficulty is 4,000 whereas on the others it's 6,400.
Due to the Clear Bonus total only displaying six numbers, it's possible to get a glitched display of the Clear Bonus if your total bonus adds up to 1 million or higher. When this happens the bonus might show that you're awarded much less points than you're supposed to but the score that you deserve still gets added.
Extra Stage
The Clear Bonus of the Extra Stage is slightly different from the maingame. There is no rank included in this Clear Bonus and since the game forces a 3 lives/1 bomb setting in Extra, the initial lives and bombs component is removed as well. In it's place the game awards you a static 10,000 points for clearing the stage and a time bonus that tracks how quickly you defeat Evil Eye Σ.[2]
| Component (JP) | Component (EN) | Formula | Minimum | Maximum |
|---|---|---|---|---|
| クリア | Clear | 10,000 | 10,000 | 10,000 |
| ミス回数 | Lives | (20,000 - (Lives lost × 4,000) | 0 | 20,000 |
| ボム回数 | Bombs | (20,000 - (Bombs used × 4,000) | 0 | 20,000 |
| クリアタイム | Time Bonus | (20,000 - Boss fight frames*) | 0 | 20,000 |
| Sum | 10,000 | 70,000 | ||
| Total Clear Bonus | Point Items collected × Sum |
* Amount of frames spent fighting Evil Eye Σ, counted from the first frame after the pre-boss dialogue until the first frame of the boss' death animation.
Rank
Rank in this game solely determines the bullet speed and not the density of the bullet patterns (it might also determine the rate of fire for any enemy that shoots at random times). Rank is represented by a number between -6 and 4 on Easy or -6 and 16 on the other difficulties. Rank increases in increments of 1 and the rank only increases over time. The actual rank the player has is reflected in the "Stage" value of the Clear Bonus. Dying is the only way to decrease rank and using bombs does not affect the rank. It is at least known that rank is reduced to 0 if the rank is 16 and the player dies afterwards. When the rank is lower, less rank is lost but to what extent is not fully understood yet. Rank is believed to increase by 1 every 20 seconds. If one were to achieve max rank before the Stage 1 Clear Bonus, the player would have to stall Flower Tank for 1 minute and 20 seconds on Easy and 7 minutes and 50 seconds on the other difficulties. This is assuming the player dies twice at the very beginning of Stage 1 and proceed to not die before that point, like most players would in a scorerun.
Skill Verdict
Skill Verdict Messages
After clearing the maingame and watching the credits, the game will give you Skill Verdict to determine how well you've played and is presented to you with a number between 0 and 100. Depending on the number you're given, you will get different verdict messages, these messages are the following:
| Skill Score | Verdict (JP) | Verdict (EN) |
|---|---|---|
| 100 | 神を超えた巫女！！ | The shrine maiden beyond divinity!! |
| 90-99 | もはや神の領域！！ | In the divine realm!! |
| 80-89 | Ａ級シューター！！ | A-class shooter!! |
| 78-79 | うきうきゲーマー！ | Cheerful gamer! |
| 77 | バニラはーもにー！ | Vanilla harmony! |
| 70-76 | うきうきゲーマー！ | Cheerful gamer! |
| 60-69 | どきどきゲーマー！ | Heart-racing gamer! |
| 50-59 | 要練習ゲーマー | Gamer who needs practice |
| 40-49 | 非ゲーマー級 | Not quite gamer-level |
| 30-39 | ちょっとだめ | Eh, nope |
| 20-29 | 非人間級 | Not quite human-level |
| 10-19 | 人間でない何か | Something other than a human |
| ≤9 | 死んでいいよ、いやいやまじで | Just die, no seriously |
Skill Calculation
The way the Skill is calculated is that for each run the game keeps track of the difficulty you're playing, the number of used continues, the number of lives and bombs spent and how well you've collected items (expressed by item_skill)[2]. The cap on this Skill number for Easy is 85 and on the other difficulties 100. How each of the four components is factored into the Skill number is shown below, however Item Skill requires a deeper explanation in the following paragraph:
| Component | Formula | Maximum |
|---|---|---|
| Difficulty | Difficulty level* × 20 | 60 |
| Continues | 10 - (Continues used × 3) | 10 |
| Lives/Bombs | (50 - (Lives lost × 3) - Bombs used) | 50 |
| Item Skill | item_skill (0-25) | 25 |
* Ranges from 0 (Easy) to 3 (Lunatic).
Item Skill
Item Skill is one of the four components mentioned that make up the Skill Verdict and is tracked by the item_skill value. There is however a subvalue called collect_skill that goes up for the collection of items. How this latter value goes up is shown below:
| Item | Collection condition | collect_skill change |
|---|---|---|
|
Below Max Power | +1 |
| At Max Power | +2 | |
|
Collected at 51,200 value | +8 |
| Collected at ≥20,000 and <51,200 value | +4 | |
| Collected at ≥10,000 and <20,000 value | +2 | |
| Collected at <10,000 value | +1 | |
|
With 5 bombs in stock | +16 |
For every 32 collect_skill points, the item_skill counter goes up by 1. When 16 items are dropped, the item_skill counter goes down by 1. Since scoreruns pick up many Point Items at max value and you only need 4 Point Items to increase the item_skill counter by 1, such runs will quickly cap this counter to 25 and will stick close to this value, as the value will occasionally drop to 24 from the items that are being dropped.