Here's a bit of a weird idea that I've been sitting on for a while now. What if Pellegarde is somehow connected to Sunshine?
There is a pattern in this series when it comes to the names of characters' magic abilities in that they are almost exclusively in English. This doesn't come across in the translation for obvious reasons, but you may have noticed it in the anime when characters say the name of their magic and it turns out to be an English word, think Escanor shouting out "SANSHAIN!". It should be noted that this pattern only applies to the names of the magic abilities and not to the names of individual techniques, which are sometimes in English and sometimes in Japanese. In NNT, this pattern held for every magic ability in the series with the exception of the Graces, which have Japanese names. This includes Sunshine, which is called 'Sunshine' when used by Escanor, but changes to 'Taiyo' when used by Mael.
Where things get interesting is with the sequel, because even though there haven't been any new Grace-style powers introduced, there has actually been a magic that follows the same naming pattern. That magic is Pellegarde's 'Homura', translated as 'Pyre'. When Pyre was first mentioned I figured that Nakaba had simply decided to switch to giving innate magic abilities Japanese names in the sequel. However, very soon after Pellegarde's debut we were introduced to Nasiens and Talisker, whose magics had English names again, and the same trend has also continued for every character introduced since then. This means that either Nakaba meant to alter the naming scheme, but then changed his mind almost immediately, or there is something special about Pyre that makes it different from every other innate magic.
Assuming that we're not just dealing with a random mistake, I have three potential explanations for the name of Pellegarde's magic. Seeing how Pyre is fire-based, the first thing that comes to mind is a direct connection to Sunshine. Perhaps something along the lines of Escanor's death causing a fragment of Sunshine to split off and turn into Pyre, which then ended up becoming Pellegarde's magic. Sunshine being weakened like this could explain how Gawain can withstand its power and also why she ran out of magic in the afternoon, when Escanor's Sunshine would have still been supplying him with massive amounts of magic. This would also set up Pellegarde as an important enemy and a power-up for Gawain, which may have already been foreshadowed with their earlier clash. The second possibility is that Pyre is essentially like a Chaos Sunshine, similar to Chaos Galand and Chaos Melascula. If Arthur wanted to create mockeries of the Demon Clan's elite soldiers, then he may have also wanted to create a mockery of one of the Goddess Clan's blessings. The third and last explanation I have relates to what I said earlier about the names of individual techniques not following the same pattern as the names of magic abilities. Maybe Pyre is not actually a magic ability at all, but just a technique that Pellegarde pretends is his real magic to hide his true power from everyone. For example, let's say that instead of fire magic he actually has magic that allows him to control the 4 elements, but keeps the other 3 hidden as his ace in the hole.
In conclusion, there is a chance that Pellegarde's magic could turn out to be something way bigger than mere fire manipulation, but there is also a very real possibility that I just spent all this time overanalyzing a small mistake Nakaba made right after returning from a year-long break.
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