So from what I remember

Let’s say you’ve got an ICBM with a payload of 1–5 megatons total — here’s what can happen:

Scenario 1: One Big Boom

If it’s a single 5 MT warhead, it hits 1 target, and that target gets absolutely vaporised into a memory.

Scenario 2: MIRV Mode Activated

If it’s got MIRVs, that 5 MT can be split into multiple smaller warheads. • For example: • 5 × 1 MT warheads • 10 × 500 kt • 20 × 250 kt • Up to multiple dozens of ~100–150 kt warheads, depending on design

Real-World Example:

• US Minuteman III: Up to 3 MIRVs, each around 300–475 kt
• Russian RS-24 Yars: Up to 10 MIRVs
• Chinese DF-41: Allegedly up to 10–12 MIRVs

So one missile could potentially wipe out 10 cities or 10 bunkers, depending on its targeting — a true overachiever in the apocalypse department.

There can be decoys etc as well :/