"That's pretty easy," Erna snapped her fingers with a confident smile. "All you need to do is trap their physical existence--which will soon be formed once their smoke form is completely discharged and re-forms into their human form.
"But how will I do that?"
"With your magic fire, of course."
"Eh?" Indra widened his eyes in disbelief. "But isn't this Infuser member's elemental type wind? How do I do that?"
Erna was silent for a moment when she heard Indra's question. The woman's brows furrowed, looking at her worriedly.
"Didn't Grandpa ever teach you how to trap enemies using your blue fire element?"
"What are you talking about?" Indra asked again.
"It's strange. I'm pretty sure our Grandpa taught you how to handle your blue flame element," Erna muttered in a half-whispered voice before Erna's face brightened instantly. "That's right. I forgot you lost almost all of your childhood memories."