Warbands: Simple Stat Blocks for Fighting Squads (5e)

From the introduction: Many great stories, in history as well as literature, feature small bands of heroes holding out against large numbers of foes. This might be holding an important objective against mobs of enemies or taking out groups of guards defending a villain’s lair. No matter the adventure or the situation, it’s useful to have mobs of foes ready to throw at the characters!