“NOOOOOOO YOU CAN’T PAY ATTENTION TO WHAT CARDS I’VE USED, THAT’S CARD COUNTING!!! USING STRATEGY IS AGAINST THE RULES!!! YOU CAN ONLY USE BLIND LUCK!!! SECURITY!!!!!!!!!”
Well yeah, it's because Zombies has exponential health scaling..
A zombie on Round 100 has 5,525,295 health. The Ray Gun's max damage is 2,000. It would take minimum 2,763 shots to kill a single zombie.
Treyarch is basically telling you to touch grass
Fun Fact: in the opening scene of Mission Impossible: Fallout, Ethan Hunt receives his mission instructions hidden inside a copy of The Odyssey.
The whole story is actually a back-to-home journey where you see Ethan finally meet his wife Julia at the end.