What it does
Trample lets a creature deal excess combat damage to the player (or planeswalker) it's attacking when blocked. You assign lethal damage to the blockers first—enough to destroy them based on toughness—then the rest spills over to the defending player.
The biggest nuance: "lethal" is measured by remaining toughness, not the creature's full toughness. If a blocker already has damage marked or took damage from another source, you only need to assign the difference. Also, you only need to assign lethal damage, not enough to actually kill it—so deathtouch changes things dramatically: with deathtouch, just 1 damage per blocker counts as lethal, letting the rest trample through. Damage prevention or indestructibility on the blocker doesn't increase how much you must assign.
In Commander, trample is huge for closing out games with big creatures, pushing through chump blockers, and especially comboing with deathtouch on voltron or stompy decks.













