[@The World]
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[*] It's basically scan data. Collect enough scan data to create a DigiEgg.
[*] None that I can think of off the top of my head, but assuming that the two Digimon are the same species, but undergo different evolutionary lines, then it's fine. For example, if your Tamer has two Salamon/Plotmon, one evolves along the Angewomon line, while the other LadyDevimon line, you're okay.
[*] Jogress/DNA Digivolution is a thing, but doing so essentially takes the two consciousnesses of the Digimon and combines them into one to create a new being. While this new Digimon has the memories of its components, it's entirely possible that it will behave differently from before.
[*] Firstly, we're calling them "Digimentals" to avoid any confusion. They're rare evolutionary items that can be obtained through rare drops or in-game events. These items are more or less akin to Mega Stones in the Let's Go! Pokemon games. As long as a Tamer has one in their inventory, their Digimon can access these forms.
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