I can buy the theory that Natsu's arm reacted to a magic type and that Zeref taught the 12 magic (it's a possibility as to why they're so strong)... but it's more believable that his arm reacted to MP levels because that is what Hiro was portraying at that moment.
Laxus could be below Spriggan level in MP, or even, or above. No one else has commented on Laxus being magically strong yet they have about the shields who apparently ooze immense MP passively (while Gray/Lucy had to activate magic for Makarov to sense anything). This I put down to plot device - Hiro wants to hype the power of the 12. There could be other reasons why Laxus' MP wasn't perceived as high, like the MBP's blocking his aura or something... I don't think it matters anyway as I view MP sensing as a plot device, and that MP isn't the only factor in a fight.
Natsu shivered in shock/fear right here...
Natsu wanted to fight Brandish after this after seeing Mest on the ground hurt. It doesn't pardon his initial shock at her MP though.
Team Natsu never really fought Ajeel, they were escaping. I think Ajeel was impressed with Gray, Natsu and Laxus' abilities, particularly here I think he's referring to all 3 (maybe Erza/Lucy as well but they did the least). Ajeel wasn't really dominated, because really he didn't get pushed by Natsu, it was a brief moment where neither did anything close to full power. Ajeel even powers up after Natsu hits him, so everything after that I presume is a step up. Laxus is the only one that really dominates Ajeel to the point where August steps in - but even that is a very brief exchange and Laxus isn't confronting Ajeel.
Laxus could be below Spriggan level in MP, or even, or above. No one else has commented on Laxus being magically strong yet they have about the shields who apparently ooze immense MP passively (while Gray/Lucy had to activate magic for Makarov to sense anything). This I put down to plot device - Hiro wants to hype the power of the 12. There could be other reasons why Laxus' MP wasn't perceived as high, like the MBP's blocking his aura or something... I don't think it matters anyway as I view MP sensing as a plot device, and that MP isn't the only factor in a fight.
Natsu shivered in shock/fear right here...
Natsu wanted to fight Brandish after this after seeing Mest on the ground hurt. It doesn't pardon his initial shock at her MP though.
Team Natsu never really fought Ajeel, they were escaping. I think Ajeel was impressed with Gray, Natsu and Laxus' abilities, particularly here I think he's referring to all 3 (maybe Erza/Lucy as well but they did the least). Ajeel wasn't really dominated, because really he didn't get pushed by Natsu, it was a brief moment where neither did anything close to full power. Ajeel even powers up after Natsu hits him, so everything after that I presume is a step up. Laxus is the only one that really dominates Ajeel to the point where August steps in - but even that is a very brief exchange and Laxus isn't confronting Ajeel.