Metropolis: I Picked up a Ghost Card

I, Jiang Chen, am a high school student and a person without sequence. Until a card fell from the sky and I changed. Others are trying their best to grab the card, but I can copy it just by looking at it. If others can't beat me, I'll buy a card. If I can't beat you, I'll "beat you with your card." But I can't let anyone know. Especially not letting law enforcers know. Because what I picked up was a ghost sign.