TOAA and The Presence play catch

TOAA and The Presence decide to play catch one day. They start with a five-pound steel plate and, after three tosses, add five pounds. The process continues indefinitely.

Every once in a while, one of the participants "accidentally" misses the throw. The weight falls from the heavens and invariably lands on the listed individuals' heads from 50 feet.

For those who are (unwittingly) involved, how much does the steel plate need to weigh to A) KO them; and B) Kill them?

(Obviously no blocking or dodging, and for the purposes of this question air resistance may be ignored. Also, the steel plate remains the approximate size of a frisbee, no matter its mass. The entities are able to get around the physics issues with this.)

A) Al Bundy

B) Master Chief (shields)

C) Rocky Balboa

D) T-800 (T2)

E) MCU Iron Man

F) Darth Vader (EU)

G) Dumbledore

H) Silver Surfer (comics)

I) 616 Thanos

J) Scathan the Approver

K) The Spectre (unbound)

L) Speedy Gonzales

M) Your favorite non-sci-fi (non-omnipotent) character