Rules change wholesale between editions, and a starter box is tied to the one it launched. Check which edition a boxed set is for before buying it second-hand.
01
11th edition — current
Announced March 2026, launched June 2026 with the Armageddon boxed set
02
10th edition — superseded
Launched 2023 with Leviathan; boxed sets and codexes still circulate second-hand