Mega Man Legends Money Making Guide
There are a few ways to make Zenny in Mega Man Legends but there are 2 methods that stand out as the best ways to make money. One of which is a farming location where you will be fighting enemies (pictured above) and the other one is participating in KTOX Mini Games which is one of the repeatable Side Quests in this game.
It's up to you which of these 2 methods you'd like to do - if you get really good at the Mini Games that is arguably the most Zenny per minute but it's very repetative. My preferred method is the farming location pictured above which is inside of the Cardon Sub-Gate. For this reason I will talk about this location first, I'll talk about the KTOX Mini Games further down this page.
Before I get started with this location there is one Special Weapon you can get for yourself that will make farming here way faster and easier - the Vacuum Arm! In order to make the Vacuum Arm you'll need to collect 3 items from trash cans scattered around the town. One part is found in the City Hall area, one in Downtown and one in Uptown; once you have all 3 give them to Roll inside the Support Car.
Vacuum Arm allows you to suck up Refractor Shards (and health) from a distance which not only means you're able to collect everything that drops before it disappears - it also means you'll be able to get it faster. This item isn't a requirement for farming here but it will definitely help out a ton and shave a lot of time off your rotations.
Entrance to the Cardon Sub-Gate
The Cardon Sub-Gate has one large room with Reaverbot "nests" that once destroyed drop a ton of Refractor Shards, as you can see in the screenshot at the top of the page. You shouldn't have any trouble finding this room considering it's the first big one you'll come across after entering the dungeon. It's also the only room with enemies inside of it throughout this dungeon.
Our rotation is going to be pretty straight forward, you'll want to enter this dungeon and clear the room in question then exit the dungeon to reset it. You can exit the same way you entered, via the elevator in the previous room. Or you can exit by going into Ruins #2 next to the elevator (jump onto the ledge then go through the door). Going through the door to Ruins #2 is marginally faster so that is what I like to do.
If you're a min/maxer then what you'll want to do for each of these runs is solely focus on destroying the nest and avoid all other enemies. The nests are what give the most money and fighting the other enemies here is a waste of your time. Destroying just the nests will earn you about 8500 Zenny a run, if you decide to eliminate all of the flying enemies too you'll get about 10k a run.
The other way of earning lots of Zenny in this game is by repeatedly clearing the Left Curve Course Racing Game at the KTOX TV Building. Once you get this Mini Game down to a science you can complete it in about 7 seconds and when you add in the menus that you have to go through it'll be about 10 seconds total time.
Each win will net you 2,300 Zenny which will add up to about 13,800 Zenny every minute if you get good enough to never fail a race and cycle through all of the menus quick enough. While this method may be quite profitable in terms of how much Zenny you earn every minute I believe that it's probably the most boring way to do it.
Ultimately the choice is yours as far as what route you'd like to take for Zenny farming. Of course you can always alternate back and forth between the areas when one gets boring too!