The sudden interruption took the pegasus out of her story as her mind delved itself in the words spoken by Rainbow about it. Not a single memory was lost untouched in her mind during the search. As a couple seconds had passed, she found the answer. "You get bitten, and then they drain you from your blood, while feeding you their own. That is how you turn. By consuming their blood as they take yours. That's what Rainbow Dash told me when I asked her."