The pathways that you take through the forest are rather fixed with occasional branches that will lead you into other areas of the woods. Making contact with a Minion will bring you into battle where you will square off against them. Once you get their health down into the red, it's time to try and capture the little suckers and entomb them in a cocoon. Each time you are successful in capturing a Minion your capture percentage will go up and enable you to collect more powerful Minions later in the game. Killing a minion yourself will grant you nothing and should not be done unless by mistake or you have no choice in the matter.
Levant is able to equip up to three Minions at a time to use in battle.
Capturing them is limited to the amount of empty cocoons you are carrying at the time. Merging minions can help you to create a new and unique minion that can be stronger and more flexible than the other two taken separately. There is a nice little screen that displays what the combined minions will look like and there is also a status screen to let you know if your choice is a good one or not. You can always elect to back out of the combination should you not like the potential outcome. Knowing how each works will give you a distinct advantage during an encounter.