>>12562675The concept of Burst is sort of like a fusion between Human and Pokémon, a transformation similar to maybe Kamen Rider or the kids in Digimon Frontier.
The transformation would be tailored to the human form, so the design of the Pokémon is applied lightly like basing a suit of armor on the Pokémon's design. In a way, it's similar to Gijinka, but more features of the Pokémon are shown. How they're applied tends to vary though, Scraggy might be a straight transformation whereas Sigilyph would have some design liberties to accommodate for a human shaped body.
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Shauntal fusing with Chandelure would mean her transformation falls more under the latter category.
Examples ahoy to give an idea.