Gear Savanna & Trash Mountain - Digimon World 1
Gear Savanna is an area that you will reach that marks you entrance into the midgame. This map is home of the Secret Item Shop (available from the 1st - 15th) along with Leomon and his training area. You can purchase lost items from this shop along with cards. When entering Gear Savanna go north once then one screen west to find the Secret Item Shop.
Much like Mount Panorama, this map is a giant circle - my advice if you're struggling to navigate it is find Leomon. The Leomon area is where you can also train which is important to memorize early since training while exploring is important.
Trash Mountain is the other location connected to Gear Savanna and there is a training location there as well as a key item, Old Rod. When you enter Trash Mountain search the ground to the left and you'll find the rod there.
Secret Item Shop: One of the main things you will be coming back to this zone time and time again for is the Secret Item Shop. To easily reach this location fly to Gear Savanna using Birdramon's fast travel and go northwest. Just before the northern exit you'll find a western exit that we can take which leads us right here. If you want video guidance check out my How To Get To Secret Item Shop In Gear Savanna for a quick video that shows you how to get here.
Elecmon
Requirement: N/A
When you enter Gear Savanna keep going north from the first screen until you find Elecmon. Talk to him 3 times in total to make him join your city, the first two times he will shock you (these damage you) and the third time he will join you. If needed, use a recovery item on yourself to make sure your Digimon isn't knocked out.
Patamon
Requirement: N/A
Just east of where Elecmon is found you'll find Patamon. In order to recruit him we'll need to beat him back-to-back in 3 different battles. Don't worry, he isn't too hard and you can still use recovery items if you run into any trouble.
Biyomon
Requirement: N/A
Head south of where you found Patamon and you'll run into Biyomon. She will run away from you two times when you speak with her. After that you'll make a plan with your Digimon to cut her off which will allow you to capture her.
Leomon
Requirement: 45+ Prosperity Points & Meramon Recruited
Leomon can be annoying to find until you become familiar with the map. When you first enter Gear Savanna and you see the sign telling you the directions of each area - go east towards "Mt Trash". Once you pass the vending machine on the next screen continue north and you'll be in the area where you first find Leomon.
Another thing to note is the area where you first meet Leomon, you must be going in the proper direction to trigger this event. If you enter the area from the opposite entrance that I instructed, the event wont trigger. You'll need to run through the area and exit then re-enter it to make the event trigger.
Once you meet Leomon, you can find him again by going west in the same area. This will take you to the location shown in my picture above which has the training areas. You can do all of the stuff I talked about above before reaching 45+ Prosperity Points.
To advance anything further with Leomon you will need to increase the Prosperity of your city to 45+ as well as recruit Meramon. After you achieve both of these goals the final Drimogemon that has been digging this entire time will be finished. When you enter Drill Tunnel from Native Forest, keep going south through the crossroads to find the area with Leomon's Ancestor's Cave.
Once you find Leomon's Stone Tablet return it to him in Gear Savanna and he will join your city.
Sukamon (Trash Mountain)
Requirement: He must be the first person you talk to in Trash Mountain
Sukamon is one of the buggy Digimon in this game and truthfully I am not even sure if he gives a Prosperity Point. To get him to join your town you must speak with him first when you enter Trash Mountain. If you speak with any other Digimon then you'll lose the opportunity to recruit him.
Don't forget to get the Old Rod near the entrance of Trash Mountain before you go too!