What NPC units spawn from each team's Nexus and march down lanes? Minions. They are the basic non-player combat units of League of Legends, generated continuously from each team's Nexus and sent along the top, middle, and bottom lanes.
Minions provide the main bridge between champions and structures. They attack enemy minions, champions, turrets, inhibitors, and ultimately the Nexus. Champions usually want to fight near allied minions because the wave absorbs turret shots and supplies experience and gold when enemy minions are last-hit.
A standard wave contains melee and caster minions, while siege, or cannon, minions appear periodically and are tougher against structures. Destroying an enemy inhibitor causes super minions to spawn in that lane, a stronger variant that helps pressure the opposing base.
The distractors are not the standard name for these units. Sentries and drones may describe units in other games, while “creeps” is informal genre terminology sometimes used by players, not League’s canonical term.