>>57875551Digimon are not biological creatures so their evolutionary paths are incredibly flexible. Unlike pokemon which evolve very rigid, all digimon share one giant evolutionary tree.
Different games and shows handle evolution differently because they tend to take place in different realities with different rules. But the card game rules probably have the easiest example to understand.
In pokemon tcg, you can only evolve a pokemon directly into another specific pokemon. But in the digimon tcg, any digimon can evolve into any digimon of the next stage they share a color with. This would be like an abra being capable of evolving into any stage 1 psychic type.
What a digimon evolves into is influenced by many factors. In the games usually each digimon has a pool of next stsges it can become with certain stats. If a digimon's stat requirements are reached then that digimon can digivolve that form.
That one branching path evolution that you're replying too is an example of a VPet line. Digimon originated as a Tamagotchi spinoff where you hatch an egg and it grows into different forms depending on how you raise it. This meant in its original iteration the first ever digimon could end up becoming a teddy bear or a cyborg dinosaur from the same egg and influenced the rest of the series.
Certain special digimon have curated lines, usually the partners of anime protagonists. Usually digimon partners in the anime have a special bond to their partners that allow digimon to evolve faster via their partner's emotional growth. This means digimon gain new forms directly from their human's character growth. This also means they can end up dark digivolving into berserk evil forms if the human starts acting unhealthy or abusive.
Hopefully that clears up some of the main forms of digivolution. Like pokemon there are a lot of special rules and ways to evolve other than the normal kind but this is the basics.
