Isekai Nonbiri Nouka - Vol. 12 Ch. 250 - Dye and Fireworks (3)

[Carcer]

Armed with those spears that can even destroy dragons' scales, the angels are likely the most powerful beings in the world now.

 

[Jstar338]

They addressed that. When attached, they act as a magic focus for the magic circulating in the inferno wolves. It's when detached that the magic goes wild when used with intent to harm, and it then explodes.

It's possible that if they're used at close range, the intent of "please don't blow up please don't blow up" keeps it from exploding