@rachel-michelle-sheets-meadows
The normal (map) characters are unlocked when you open a certain area on the map by raising your level. Each character you upgrade gives you one level. After reaching the area, you must release the bot using pigs. This works until level 175. After that, there is no more character on the map to be freed.
The new area is an exception. First you have to gain access to the island using Plasma. You can obtain plasma through daily quests, and buy on events. After that, you must collect bats (instead of pigs) to unlock Nautica, the other new character. Bats can be obtained mainly with cave runs and daily quests.
The event characters can be obtained only through events (of course). They usually are available on the token exchange, and can be earned with money too. Your level don’t affect this at all, so you don’t need a high level to obtain those characters (but it is so much harder with low level bots to perform well on events).
Definitely you don’t have to spend money to get everything, but it is very time consuming, and you must be very patient. I have all bots so far (with the exception of the one from the current event), and I have not upgraded everyone to level 15 yet. Everything I earned so far was for free, I have not spent a single cent in the game.
EDIT: Just to complement the information, there will still be a huge clouded area, that is not developed yet. So basically, you will run out of the option to “Explore” a new area after level 175.
