Introduction
Jack Bros. is a 1995 twin stick shooter game developed and published by Atlus for the ill-fated Virtual Boy. It's the night of Halloween and Jack Frost, Jack Lantern, and Jack Skelton have to rush back to the World of Fairies before midnight to avoid banishment. The trip takes place across 6 areas and 60 floors. This is also the first Shin Megami Tensei game to officially come out in English.
This TAS uses Jack Skelton in the game's "For Super Players" mode, accessed via a code on the main menu. While it's weird to select the character who can't shoot in a run 'n gun, he's got a powerful knife to make up for it.
Run notes
- Emulator used: BizHawk 2.9.1
- Virtual Boyee core
- Heavy RNG manipulation for item drops
- Takes a lot of intentional damage, though most of it is guarded
Mechanics and Techniques
- Character choice
- The three playable Jacks and the secret character Pixie all play fairly differently.
Jack Frost: He has the best rapid fire rate with projectiles but they do little damage. His special attack also primarily freeze enemies in place though also doesn't do much damage.
Jack Lantern: His projectiles do a decent amount of damage. His special attack is also decent damage with a fairly short animation time. While special attacks are his primary source of fast damage on bosses, the 9 star limit means he can't quite keep up the damage pace for longer fights.
Jack Skelton: This is the character used for this submission.
Mack the Knife here uses a short range melee knife attack rather than a projectile. This limited attack range is made up with having the best damage per attack since it can be "rapid fired" by continuously holding a direction. The knife does enough damage to one-shot most enemies in the game and outpaces Jack Lantern's damage on bosses without needing to use special attacks.
The main drawback is that while Jack Skelton's special attacks are also really powerful they have an incredibly long animation time such that it's faster to just stab with a knife. The special attacks are used in a few places, mostly to take out the annoying Cyclopses on a floor since they can stun through invincibility.
Pixie: Pixie is the secret character that requires using a special password and input. While she can only shoot one projectile at a time those projectiles do a lot of damage. Her other benefit is that she doesn't have to stop for message boxes since normally she's the one who tells the Jacks that info, making her actually the fastest from that alone.
- Items and RNG manipulation
- Enemies can drop helpful items to speed up the game. The highest priority is the invincibility potion as that grants both invincibility and extra movement speed. The next priority is the Jack shield which gives 3 orbs that can block attacks without the stun animation from getting hit, allowing for damage boosting without stopping and for allowing the use of a lot more i-frames than normal. The last kind of helpful item is the special attack stars which simply give an extra special attack, up to 9 stars held at a time.
RNG manipulation mostly consists on the frame the enemy dies so waiting on the attack is generally how drops are manipulated. Player position and attacks on certain frames seem to also affect this but I just worked with delaying attacks for item drops. Using positioning for manipulation is primarily used for Mystic Morgan teleport positions.
The main item drop manipulation that's obtained is invincibility potions. The speed boost is powerful enough that taking a detour or wasting a little time just to get a drop is made up by the sheer speed boost. However, there were some floors where I just couldn't get the drop. The main culprit is that I'm pretty sure that Slimes simply don't have them in their drop table, though other floors I just didn't have the luck on my side. Sometimes I also go out of the way for a Jack shield drop as the effects of the invincibility potion go away upon dropping down a floor while shields persist. Some floors benefit from having a shield ready to avoid getting stunned by an enemy attack while going fast.
- Special and secret bonuses
- This one I'm still fuzzy about but I think I got a rough idea of how it works.
Special bonuses are extra time bonuses that I think are granted for getting a certain number of enemy kills in an area. These seem to be unavoidable since a lot of fast movement involves taking out enemies on the way, either by attacking or with contact damage under the effects of the invincibility potion.
Secret bonuses are extra time bonuses granted from fulfilling certain tasks on certain floors. While I don't know all of them the ones I primarily knew to avoid were the ones that were either pacifist secret bonuses or ones that require killing certain enemies. The delay on the bonus is skipped when possible since going out of the way to avoid those conditions saves more time.
- Normal and Super mode differences
- The main thing the code changes is enemy and obstacle layouts. For the most part this makes Super mode trend towards more difficult levels. However, some of levels that were puzzle levels in Normal were changed to more action oriented levels and vice-versa. There are also cases where Super mode floors can be cleared faster by virtue of having a closer enemy for an invincibility potion drop. While this submission was done on Super mode, there's a case to be made for future submissions from other folks using a different permutation of character and game mode.
Possible improvements
- I didn't work out specific item drop odds from enemies but it would certainly help on the RNG front.
- Naturally, better RNG overall would help out just to get better drops faster.
- Of course, there can always be better per-floor routing that I simply didn't catch.
- The Spider Orb and Belzoff boss battles have notable periods where they're not getting hit. Those two bosses have the most potential to save time between all the bosses.
- Spider Orb could be made faster by finding a strategy that avoids the stun from getting hit after losing the Jack shields.
- Belzoff doesn't have getting stunned by hits, instead opting for some dodging before going back to the offensive. Belzoff also has two pairs of paradice that the knife collision prioritizes over anything else, leading to some situations where even at the right attacking distances damage couldn't be dealt.
Note for encoders
I have an input file that has post credits input to show the Pixie selection input after the "The End" screen that I used for my personal encode.
Samsara: Judging, hee-ho!
Samsara: Nice work on the potion manipulation! It's what caused me to give up when I quietly tried doing this run a while ago, so I'm happy to see it done well here. Accepting!
fsvgm777: Processing. Also changing the branch to properly reflect the name of the Super mode.