죽였는데

killed, but

→ 죽이다
죽였 Past tense + 는데 Background/contrast connective
verb · informal, past tense Rare #28,868
killed, but The ending -는데 links this clause to what follows; depending on context, it can also mean “and” or set up background information.
KO: 어제 모기를 죽였는데 오늘 또 나타났어요.
EN: I killed a mosquito yesterday, but it showed up again today.
Conjugation of 죽이다

이 사람이 어떤 아이를 죽였는데 엄마가 도와줬어

This person killed a child, and the child’s mother helped them.

— 친절한 금자씨 (2005)

문제가 터지면 신나게 댄스로 혼을 빼 빈틈 딱 감추고 각본 대로 밀어붙여 사람을 죽였는데

When trouble breaks out, I dance like crazy to distract everyone, cover up any openings, and push ahead according to plan—I killed someone, but…

— 시카고 (2002)

한번은 술집에서 세 명을 죽였는데 연필 하나로 죽였다

Once, I killed three people in a bar using just one pencil.

— 패딩턴 2 (2017)