Watch Dragon Warrior II get beaten in 3 hours

[Dwedit 4]

Here's a video of Speedrunner NESCardinality beating NES Dragon Warrior II in about 3 hours, setting the world record time.  Not a TAS, no save states or re-recording here.  Watch him perfectly manipulate the game, fighting only Metal Babbles and killing every one of them.

https://www.speedrun.com/run/nz16207m

 

[TriforceBun 21]

Whoa, how the heck did he avoid battles for so long?

[Dwedit 4]

Avoiding the battles early on is the easy part.

The game shares the RNG (random number generator) seed with the save file checksum, so whenever you save the game or load a saved game, it will overwrite the RNG with the save game's checksum.

However, there are certain saved game checksums that will freeze the RNG and cause it to always spit out the same number.

You can get one of those checksums with a certain combination of Name and Message Speed.  One such name is TUT (message speed Fast).  The runner uses a different name that also freezes the RNG.

 

Saving the game generates a new checksum, and unfreezes the RNG.

 

Also note that every character that moves randomly was also always walking to the right in the video.  (if you use TUT as the name, they walk south instead)

 

However, if you freeze the RNG like that, even though you avoid battles, if you actually get into a battle (first forced battle is at Lianport), the game freezes because it can't get a random number that it needs to snap out of some calculations.

 

The guy has to save in order to proceed with the game and get the ship.  So he now has a known random number seed, and he does precisely determined movement to get the random numbers where he wants them for the Metal Slime and Metal Babble fights.

[Woodus 1,651]

Thanks for the explanation on that