Important note (read before voting)

The game completion time is apparently longer due to more accurate emulation, which makes the loading times longer, but gameplay is actually shorter. For anyone who doesn't know: using a better emulator even if this means to apparently increase the time of the run, is highly recommended by the rules of the site.
Here is a VBA-rr version of the submission movie, made by me before migrating to BizHawk, which shows game completion 22 frames shorter than the current publication: http://dehacked.2y.net/microstorage.php/info/698388924/thunderaxe31-rolanscurse_walkintrick.vbm
This also explains why the rerecord count is so small.

About the game

Rolan's Curse is a Game Boy hack 'n slash stabbing game in which you take the role of Sir Lagsalot a knight that has to defeat an evil lord named Barius, in order to free the land of Rolan.

Game mechanics

The gameplay is very similar to The Legend of Zelda, but slower and simpler. You start with a sword, an attack power of 1 and 4 HP (2 hearts). Attack power and HP can be increased temporary or permanently by different items; temporary increments will disappear after you kill a boss and proceed to the next chapter (there are 4 in total) and permanent increments will stay for the entire play. You can move in the four cardinal directions for steps of 8 pixels (half map tile) and attack enemies by using an equipped weapon. Killed enemies may drop a potion or an armor; in rare cases other items. Here is the list:
  • "Weapons": Are to be used by pressing B button. When you pick one of these, it will replace your current weapon and increase your temporary attack power by 1.
    • "Sword": Can attack only withlin 8 pixel in the direction the hero is facing.
    • "Wand of Uzi": Looks like a rod with a jewel on the top. Can attack at distance; attack rate and power seems to be the same as for the sword.
  • "Special Items": Various items set to be used by pressing A button. Then you pick one, it will replace the one you already have, if any.
    • "Potion of Life": Looks like a jug. When used, refills HP completely and disappears.
    • "Shield of Valor": A shield with a cross on it. When you hold A button, it will protect frontally from ranged attack, but not contact. If you use the D-pad while you still hold A button, the hero will turn but not walk.
    • "Magic Axe": Looks like a pickaxe. Can used to remove some obstables.
    • "Chameleon's Ring": A ring with a jewel. When you press A, you the hero will turn into a background object and become immute to enemy contact until you press A again to come back normal. This doest not protect from ranged attacks and you can't attack while transformed.
    • "Power Crystal": Looks like an orb. To use it, you need to keep A until charged, then release. Does more damages than other weapons, but seems useless due to being slow.
  • "Other Articles": These items take effect in the moment you pick them up.
    • "Chain Mail": It is supposed to be an armor, but looks like a mushroom to me. When picked up, it increases your HP temporary by 1 (half hearth).
    • "Merlin's Cloak": It is supposed to be a cape, but looks like a slice of watermelon. When picked up, gives temporary invulnerability to any attack.
    • "Elvenade": Looks like a vial. When picked up, restores 4 HP (2 hearts).
    • "Heart": Guess what? Gives you a heart. Permanently <3.
    • "Gauntlet": Looks like a... hand. Increases attack by 1 permanently.

Game objectives

  • Emulator used: BizHawk 1.11.8
  • Improving the current publication's completion time
  • Takes damage to save time
  • Major skip glitch
  • Final boss skip glitch
  • Heavy luck manipulation

Known tricks

  • Taking damage: well, this is more like common sense; you spare a lot of time by not attacking and in the meantime you take the healing items you need for not dying.
  • Luck manipulation: most enemies can drop an item if they are killed in the right moment. There is a 2-byte value located at C0A3 which is relative to the moment the killing blow is dealt (first frame in which the sword is visible). This value changes every non-lag frame and it is not affected by any action; however if some unknown requirements aren't met, the drop won't occur. Apparently, the amount of enemies killed before seems to be involved.
    • (not used) It is possible to wait before entering an area, if this makes the enemy killing less problematic, like at frame 5968, in which you can't wait even a frame before killing the enemy, otherwise you will get hit by the enemy incoming from the right.
    • (new) If you have have enough spare HP and the RNG allows it, you can walk into the enemy to save walking time. Used at 12982.
  • Quick hitting: sometimes is possible to execute the next attack faster. This is probably due to a bug; more research about this may improve the run by some frames.
  • Controlling enemy spawning: some enemy spawn only if an other given enemy is killed. This can sometimes used to actually prevent an enemy spawning. This is used only once in the movie: if at 4052 you don't kill the bat, the other bat won't disappear in the right moment.
  • (not used) Attacking from the corner: if you change direction when you are near a wall, the hero will turn without having to take a step. This can allow to quickly turn for attacking an enemy from behind a corner, for enemies like at frames 6512 and 10693.
  • Quick turning: it is possible to invert direction during a step. This allows to pick up items and turning for attacking in a different direction, without having to make a full step. Used at 13021 and 14334 for items and at 15285 and 15354 for attacking.

Game end glitch

If the killing blow is dealt to the first boss in the same time the player's HP goes to zero, the game will mistakenly think the last boss is actually beaten. In order to do so quicker, the player is provided to have enough HP to walk into the boss and not die on the first contact damage. Otherwise, it would have to wait for the boss to resume moving, which would waste a lot of time.

Improvements done

The movie is mostly the same to the current publication, except for two improvements I made at:
  • 7867: 1 frame saved by killing the ghost without touching it.
  • 12982: 21 frames saved by walking into the enemy instead of waiting in front of it and picking up the potion by quickly inverting direction two times.
  • 15730: 1 frame saved by optimizing the last attack. not really...

Possible improvements

  • Maybe it would be possible to save a significant amount of frames by avoid killing one or two enemies. This is a problem because most enemy drop don't occur if you omit one or more kills. More thorough research of the item drop mechanism may uncover new ways to improve this run. Here is a run recored with VBA-rr in which I managed to save even more frames, until I got forced to lose them all for the last potion drop: http://dehacked.2y.net/microstorage.php/info/145168094/thunderaxe31-rolanscurse-argh.vbm
  • The same goes for the attack rate: sometimes is possible to attack faster, probably due to a bug. Note how the second attack to the wolf at 8625 is 4 frames slower than in Aqfaq's run (first publication). mmbossman (author of the current run) also noticed this, but was unable to solve the problem. Optimizing this exploit may save frames for any situation in which it is needed to hit an enemy multiple time, like for that wolf and the boss. It may even allow to kill the lizardman at 12718, which would result in not needing a potion.

Suggested screenshots

13011 or 13020

Thanks

What's next

While I may be able to improve this run in future, my main goal is to make a 2-players glitchless run out of this game. Rolan's Curse is probably the only adventure GB game which implements real-time multiplayer capabilities, and I'm sure it would be very interesting and entertaining to create and to watch. Read the relative forum thread for more info.

Note for the judge

I wrote on the forum that using BizHawk would result in a different RNG, but I was wrong. I found no difference in gameplay while making this run, except for the boss fight, in which I had to change the timing of a couple of attacks because of lag, but this didn't result in more frames. So in the end this run is longer just due to loading times.

Samsara: File replaced with a 1 frame improvement.
Masterjun: Judging with energy!
Masterjun: File replaced with the old movie, as the 1 frame improvement movie didn't finish the game.
Masterjun: Total time is longer due to emulator differences. However this movie still improves the previous run. Accepted to the Vault as an improvement over the previous movie.
fsvgm777: Processing.


TASVideoAgent
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This topic is for the purpose of discussing #5274: ThunderAxe31's GB Rolan's Curse "game end glitch" in 04:23.40
Spikestuff
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This is well executed. But for me like the other two before it. I'm just not entertained. I'm voting Meh, but I must write great job on the run.
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Thanks. I knew the response to the movie was going to be soso, but I still wanted to submit this in order to gain more attention to my 2-players project. I think it is extremely unusual to see a GB adventure game with 2-players real-time capabilities, and so I'm sure it would be very entertaining, unlike this.
my personal page - my YouTube channel - my GitHub - my Discord: thunderaxe31 <Masterjun> if you look at the "NES" in a weird angle, it actually clearly says "GBA"
mklip2001
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Good job with the minor improvements here. The manipulation looks good. It's just a shame the main character is so slow; if you had to complete more than one stage, the game would get horribly boring. I'd be quite interested to see where a 2-player run of this game goes though!
Used to be a frequent submissions commenter. My new computer has had some issues running emulators, so I've been here more sporadically. Still haven't gotten around to actually TASing yet... I was going to improve Kid Dracula for GB. It seems I was beaten to it, though, with a recent awesome run by Hetfield90 and StarvinStruthers. (http://tasvideos.org/2928M.html.) Thanks to goofydylan8 for running Gargoyle's Quest 2 because I mentioned the game! (http://tasvideos.org/2001M.html) Thanks to feos and MESHUGGAH for taking up runs of Duck Tales 2 because of my old signature! Thanks also to Samsara for finishing a Treasure Master run. From the submission comments:
Shoutouts and thanks to mklip2001 for arguably being the nicest and most supportive person on the forums.
EgixBacon
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I never knew about any of the two previous runs, so going by first impressions alone, I'm going to vote Yes. I'll admit, the game is pretty slow-paced, but I like the fact that a GEG could be discovered in a game that's not from a popular franchise (by which I mean Mario, Zelda, etc.).
FanFiction|Youtube Still on Win7! Take that, Microsoft!
Post subject: Minor improvement
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I just managed to improve my run by 1 frame, by optimizing the last inputs. I ask if it is ok to update the file. Here is a download link: http://www.solidfiles.com/v/VvDV5yqPywZYP
my personal page - my YouTube channel - my GitHub - my Discord: thunderaxe31 <Masterjun> if you look at the "NES" in a weird angle, it actually clearly says "GBA"
Samsara
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Could you upload it here instead? http://tasvideos.org/userfiles/
TASvideos Admin and acting Senior Judge 💙 Currently unable to dedicate a lot of time to the site, taking care of family. Now infrequently posting on Bluesky
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done. http://tasvideos.org/userfiles/info/34655463396696602 by the way, is there any problem with the temporary file hoster I've chosen? I think it's good...
my personal page - my YouTube channel - my GitHub - my Discord: thunderaxe31 <Masterjun> if you look at the "NES" in a weird angle, it actually clearly says "GBA"
Samsara
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ThunderAxe wrote:
done. http://tasvideos.org/userfiles/info/34655463396696602 by the way, is there any problem with the temporary file hoster I chosed? I think it's good...
Nothing particularly wrong with it. Userfiles are just much more convenient for us. Sync verified, file replaced.
TASvideos Admin and acting Senior Judge 💙 Currently unable to dedicate a lot of time to the site, taking care of family. Now infrequently posting on Bluesky
warmCabin wrote:
You shouldn't need a degree in computer science to get into this hobby.
Masterjun
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The new movie doesn't seem to die while defeating the boss, thus not triggering the actual end credits, but instead the ending of the normal boss fight. Editing the last hit to be one frame later triggers the ending again. So was that improvement really an improvement?
Warning: Might glitch to credits I will finish this ACE soon as possible (or will I?)
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I'm really sorry, it seems I've screved up. Please put back the old movie file *facepalm*
my personal page - my YouTube channel - my GitHub - my Discord: thunderaxe31 <Masterjun> if you look at the "NES" in a weird angle, it actually clearly says "GBA"
Noxxa
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Could you re-upload your old file to userfiles? Samsara is away for a while and I haven't got a backup of the old file.
http://www.youtube.com/Noxxa <dwangoAC> This is a TAS (...). Not suitable for all audiences. May cause undesirable side-effects. May contain emulator abuse. Emulator may be abusive. This product contains glitches known to the state of California to cause egg defects. <Masterjun> I'm just a guy arranging bits in a sequence which could potentially amuse other people looking at these bits <adelikat> In Oregon Trail, I sacrificed my own family to save time. In Star trek, I killed helpless comrades in escape pods to save time. Here, I kill my allies to save time. I think I need help.
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my personal page - my YouTube channel - my GitHub - my Discord: thunderaxe31 <Masterjun> if you look at the "NES" in a weird angle, it actually clearly says "GBA"
Masterjun
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Replaced with the old movie file. Judging incoming.
Warning: Might glitch to credits I will finish this ACE soon as possible (or will I?)
Post subject: Movie published
TASVideoAgent
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This movie has been published. The posts before this message apply to the submission, and posts after this message apply to the published movie. ---- [3259] GB Rolan's Curse "game end glitch" by ThunderAxe31 in 04:23.40
Post subject: Re: #5274: ThunderAxe31's GB Rolan's Curse "game end glitch" in 04:23.4
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TASVideoAgent wrote:
most enemies can drop an item if they are killed in the right moment. There is a 2-byte value located at C0A3 which is relative to the moment the killing blow is dealt (first frame in which the sword is visible). This value changes every non-lag frame and it is not affected by any action; however if some unknown requirements aren't met, the drop won't occur.
I got bored.
Language: NASM

359e LD HL, 0x001a 35a1 ADD HL,DE 35a2 LD A,(HL) 35a3 LD B,A 35a4 AND 0xf0 35a6 JR Z,56 35a8 CP 0xf0 35aa JR Z,5 35ac CALL 0x0998 0998 CP 0xff 099a JR NZ,2 099e PUSH BC 099f LD C,A 09a0 CALL 0x0985 0985 PUSH HL 0986 LD HL, 0xc0ad 0989 LD A,(HL) 098a AND 0x0f 098c INC (HL) 098d LD HL, 0xc0a5 0990 CALL 0x091f 091f ADD L 0920 LD L,A 0921 JR NC,1 0923 INC H 0924 LD A,(HL) 0925 RET 0993 XOR 0xff 0995 LD (HL),A 0996 POP HL 0997 RET 09a3 CP C 09a4 POP BC 09a5 RET 35af JR NC,47 ; Is carry set? Yes = drop item.
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Thanks for the code! I've started studying it and I'm finally beginning to understand assembly! Also, I didn't expect the algorithm to be so complicate... But who cares. When I'll come to fully understand it, I'll describe it in the relative game topic. See ya
my personal page - my YouTube channel - my GitHub - my Discord: thunderaxe31 <Masterjun> if you look at the "NES" in a weird angle, it actually clearly says "GBA"