Hey! I'm just getting into trying Bubble Bobble 2 as a speedgame and I'm wondering if theres some kind of a guide somewhere that could help me understand some of the mechanics I see being used in the speedruns on here? Such as intentionally dieing to keep lives count low, not grabbing the crystals, bouncing on bubbles a certain amount of time?

Also, would I be allowed to submit runs done on the NES Classic as I can transfer a rom over to it to use it as my emulator of choice. Would this be classified under Emulator runs? Thanks in advance to anyone that helps me out!

Hey Yeves!

Unfortunately there's not a lot of info other than these speedruns readily available out there. You've listed a lot of good ones, but I'll elaborate on those a bit.

LIVES: If you get 8 or more lives, the game will let the enemies out of the bubbles sooner and summon the white whale sooner. Hearts also count as lives. I recently ran a 27:16 run with like 17 lives at the end, so it's not to say you HAVE to die to keep the life count below 8...just that on some levels it might help you manage item drops or other enemies and keep the enemies in the bubbles longer.

STAR ROD: Probably the most important one for an Any% run. NOT collecting 7 crystals will (typically) summon the star rod on the next level after the 7th skipped crystal. I think there are two possible ways of where you ideally want to get the star rod...

 Level 41:  If you can get the 7th crystal to spawn on level 39, a star rod will appear on level 41.  This will let you skip levels 41-60, including the bird boss fight AND the basketball mini game.  It'll plop you right into Level 61.  The later levels are tough, but skipping the boss fight and minigame are huge saves.  I've done this method before I really knew what I was doing in the game, but have not gone back to try it out again. Your first 40 stages will need to go a bit slower to get that many crystals to show up.

 Level 61: By getting a 7th crystal on level 59, the star rod will appear on level 61 and skip you to level 79 (Super Drunk fight).  A crystal on 61 is not the worst either, which is what i got in my run.

 * Just an FYI, if you happen to get the 7th crystal on like, say, Stage 57...the star rod would show up in level 58, and only skip you to Level 61.  It just moves through the next boss fight and minigame (or to the final boss fight), depending on when you get it.

ITEM DROPS: Ok...some of this is pure guessing or conjecture. I also don't know which items trump other items. This is the biggest question mark in the game yet, but a bit has been figured out. I won't list all of the items here, just the ones that I typically see in a run. SHOES: Typically bouncing on bubbles 5-6 times will spawn a shoe. If an item has already spawned in a level, the shoe will typically appear on the next level, unless trumped by another item drop. HEART: This seems to be tied to the amount of food you pick up. Not 100% on the amount needed to spawn one. CANDY: Not sure on this one. Amount of bubbles blown/popped? Jumped on? CRYSTAL: Not totally sure here either, but it seems there's some element of time related to this one. Spending more time on a stage, or hitting a certain game time, sometimes causes a crystal to pop up. Sometimes some food needs to be collected before the crystal will come up. UMBRELLA: After collecting two shoes back to back, an umbrella typically appears in the next level. Sometimes this doesn't happen, but the game will delay the umbrella drop until other item drops have cleared out. It seems to be counterproductive to keep trying to get shoes if you get 2 back-to-back and the umbrella doesn't appear in the next stage...the umbrella just kinda comes up when the game's ready for it. Sometimes the game will give you the umbrella if you don't collect the shoes back to back, but I'm not sure how that exactly works either.

MISC: The only other thing I try to make sure to do when running is end the level as close to the lower left corner as possible. It speeds up the transition between stages. Not a huge deal, but it adds up over 40-50 levels.

Anyway, I think that's most of what I know right now. Maybe you already knew that stuff too, but at least it's here for anyone else to start with if they'd like to try the game. If anyone else knows other info about the drops or game, please feel free to chime in!

Oh, and as for the emulator question....I think that would be ok. Yes, it would still be considered an emulator. Maybe just note that in the description of the run or something. My first submission on this game was on a Classic. I'm not really aware of differences between the Classic emulator and Mesen (which is the emulator I used and is generally recommended per the game rule submission info).

If anyone else has a more educated stance on the Classic emulator vs. Mesen or others, let me know.

Thanks! Most of the info I knew in my initial post I kinda partially figured out from analizing your latest run!

Thanks for the help! I'll give it a try soon and start practicing!

Just as a sorta guide, is there any sort of pattern for where I should aim to get the star rod? Obviously its got a lot of random elements to it, but as you said, there are a lot of different outcomes depending on the level I spawn it.

Is there a certain pattern for which levels will send me to the final Super Drunk fight? Like, will it only send me to that fight if I get it in the 60's or 70's? Or am I overthinking it and it simply skips to the next boss fight? In which case, do the 60's not end in a boss?

Thanks again for any help! I super appreciate it!

Yeah, I guess it's not through the next boss fight...it's through the next minigame, or to super drunk if you get it in 61 or later. I think the level targets it set above (close to 41 or 61) would be the optimal times to get it.

Henlo~ =3

So, I was interested in possibly trying to run this game sometime, and so I was messing around with it a bit in an emulator, and while I am absolutely not well-versed in 6502 assembly language, I think I can at least confirm or correct a lot of the speculation above and hopefully provide some additional information that will be useful.

STAR ROD: 0x0544 seems to increment each time that a crystal despawns without being collected, and when the value of this address reaches 7 that appears to be sufficient to allow a star rod to spawn, so the information above seems correct.

SHOES: 0x0545 seems to at least most of the time be increased by 2 each time that you bounce on a bubble, and when the value of this address reaches 10 that appears to allow the shoes to spawn, so it seems to be correct that the shoes require either 5 or maybe 6 bounces sometimes on a bubble to spawn.

HEART: 0x053F seems to increment whenever you collect a food item that has been dropped by an enemy (I'm not sure if other items also increment it, but the food that falls from the sky occasionally apparently doesn't.) When the value of this address reaches 10 that appears to be sufficient to allow a heart to spawn. So it seems that a heart will appear for every 10 food items dropped by an enemy collected.

CANDY: 0x0546 seems to increment each time that you fire a bubble, and when the value of this address reaches 50 that appears to allow candy to spawn, so candy apparently appears based on bubbles shot.

CRYSTAL: This one is a little complicated and seems to involve two different memory addresses working together sort of.

0x0014 - A timer that I believe starts from 0 when the game is booted, increments every frame, and loops back around to 0 after reaching 255. 0x0543 - A counter that (generally) increments when the timer at 0x0014 hits the value of 254. So most of the time it will increment every 256 frames. When this counter reaches 16, that appears to be sufficient to allow a crystal to spawn, so essentially a crystal can (usually) be spawned every 4,096 frames assuming that you are currently in a level in which another special item such as the ones above hasn't already spawned.

An exception to the 256 frame rule is when first starting the game. After you press start on "1 PLAYER" the first increment to 0x0543 seems to occur in 656-911 frames depending on what the value of the timer at 0x0014 was on the frame of your button press. Pressing start when the timer has a value of 111 appears to produce the slowest increment taking 911 frames, with this time decreasing by 1 for each subsequent frame until the timer reads 110 which should give you the fastest increment of 656 frames. I have no idea what would be an ideal timer value to start the game on, since I guess that it would depend on what the optimal route even is, but I imagine that you could probably experiment with this and come up with some sort of strategy for starting the game at around the ideal timer value that you want from a reset.

Anyway, based on the above information, probably the most important takeaway for routing purposes is that it is basically going to take a minimum of around 8 minutes in order to have skipped the 7 crystals required to spawn a star rod assuming you can spawn each one of them immediately once it's ready and not waste time waiting for them to despawn at the end of levels.

Also, the timer at 0x0014 continues to run even while the game's paused, but the game has to be unpaused when it hits 254 I believe in order for 0x0543 to be incremented... I mainly just mention this because I don't know if it could potentially be a strat to intentionally pause the game repeatedly in order to build up the time for a crystal to be spawned without taking too much time and spawning Sawbones (the white whale.)

UMBRELLA: 0x054B seems to increment each time that you collect the shoes, and when the value of this address reaches 2 that appears to be sufficient to allow an umbrella to be spawned, so it does seem to be correct that collecting shoes twice (I don't think they have to be collected consecutively) spawns the umbrella.

The order of precedence when you meet the criteria for spawning multiple items simultaneously seems to be:

HEART > CRYSTAL > STAR ROD > SHOES > CANDY > UMBRELLA

I guess that hearts could be strategically spawned in order to delay a crystal or star rod spawn, but otherwise I imagine you'd generally want to avoid spawning hearts in a speedrun by avoiding/minimizing the collection of food dropped by enemies, or you can clear the counter for the heart spawn by continuing I believe.

I believe it's correct that if you have collected two shoes, you shouldn't spawn any more of them until you collect an umbrella.

Candy unfortunately seems to block the umbrella, but it could be possible to overflow your bubble shot counter past 255 and back to 0 to avoid spawning candy, with pretty careful management I imagine.

In terms of trying to route this, it seems like you could either deliberately take parts of the game slower in order to spawn more crystals and go for more star rods or else just continue to spawn the one star rod and otherwise spawn as many umbrellas as possible... I'm not really sure what the ideal strategy would be.

I'll probably continue to look into this stuff but just thought sharing this information could be useful! ^^

Awesome, RedPepper. Some good stuff to ponder on here. 2 star rods is an interesting idea as a strat. The order of item priority is super helpful. It does seem like avoiding hearts may help for crystal collection, but at the cost of stage time. Probably worth it if it helps squeeze another umbrella in the route.

Can you tell what spawns the tree, gate, pencil, and trophy items? I've had a tree or gate ruin getting a crystal in level 59 several times, which is annoying.

Also, can you confirm that getting an umbrella resets the crystal timer? I believe this is the case. Any other items reset it? Maybe star rod?

Also just for clarity, dying and using a continue would totally reset your despawned crystal count, right?

Thanks for diving in, and please share any other exceptions or findings you may come across that seem beneficial!

EDIT: I tried running a 2 star rod method last night, and while I got the first one with a time save skipping from 21-41, getting crystals for the second one took way too long. I think there's certainly a better 2x star rod path than what I did, but seems better to use the info above to help spawn umbrellas and crystals in a more optimized pattern with just 1 star rod.

A bit late to the party here, but I've been looking into the code of the game, and this is the only place I've found on the internet that actually discusses these things. :P

Of course, a lot of stuff already covered here just makes my findings irrelevant. :P Though a few things I know that haven't been mentioned.

The full item priority order is:

Hearts > Chalice > Door > Pencil > Crystal > Star rod > Shoe > Candy > 1UP > Clock > Cane > Tree > Umbrella

If one of those items is queued up, it will always appear instead of the next in line. That's what makes umbrellas a lot more rare than they should be - crystals get queued up every 68 seconds, so they usually steal the priority.

The extra credit PENCIL appears after clearing 20 stages, so it's pretty unavoidable outside of skipping stages. The DOOR appears after grabbing two crystals, so if you're trying to let them time out, it shouldn't appear. But of course if you're trying to time the appearance of the star rod it could be an issue. The TREE appears after taking 20 hits (whether you had extra hearts or not). The CLOCK appears after picking up 7 (or 8? first one sets the counter to 0) of the same type of food item (like the hearts, food dropping from the sky don't count), and picking up another item type removes the clock from the queue. This is why one of the only places you'll usually see it is on Round 11. The CANE is triggered by bursting four or more enemies simultaneously, but the counter is constantly reset to 0, so it requires very precise timing and no other items spawned on the current stage yet, which makes it extremely rare. Probably much more rare than intended. I've only seen it on the first stage because no other items were queued up.

The game works a bit different from other games in the series which decide the item to spawn when a stage starts. This game checks periodically if an item is queued. So if no items have spawned yet and you jump enough times on a bubble, a shoe will appear on the same stage.

Still unsure what triggers the chalice or the 1UP, but threshold for both counters is 2.

Also not sure what the tree does. Anyone know?

Ok, the Chalice appears after a stage timer has been close to running out twice. The 1UP is still eluding me. If I set a certain enemy/object state to $16 (which also freezes it) and get hit by it, it'll increase the counter. Not sure what actually sets that state organically in the game - I'd have to play through it on emulator. It's not the clock :)

Seems that all the tree/broccoli does it ensure you get 4 food drops after clearing the stage

1 up counter is increased by dying to Sawbones. Trophy counter is increased when the hurry up timer plays, but the amount required to spawn the trophy also goes up as the game goes on. I try to take some advantage of this in the warpless run, but it's really hard to route in trophies due to the counter possibly increasing after a level is cleared but before the level moves on.

There's no official BBP2 discord, but I've disassembled the game and discussed it quite a bit in Jaek's discord. There's a lot of stuff I've found/mapped out if you're curious.

An important note on the crystal counter is that it doesn't advance after an item despawns or is collected on that level. That's used quite a bit to space out the crystals correctly. The Any% route in the guides is the best JohnnyGo and I could come up with, but there may be some other good routes or slight improvements to what we have. Would love to know what an optimized double star rod run would be like, although I think its slower than what we've got, and would involve a ton of just standing around.

Warpless is still the wild west, but there are some good thoughts to start with.

Once the priority list and item conditions are second nature, which it sounds like you understand pretty well already, the run really opens up and gets fun.