Troop stack
From The Heroes of Might and Magic III wiki
Troop stack (or creature stack or stack) is term for creatures arranged in groups in heroes' armies. Each troop stack can hold one or more creatures, but all the creatures in the troop stack must be of the exact same creature type. A hero's army must have at least one troop stack and can include up to seven. In battle, a hero leads the battle by commanding their army rather than fighting directly.
All troops can stack up to 9999 in Shadow of Death and Armageddon's Blade
