Deathtouch is a static ability that makes any damage from a source with deathtouch lethal to creatures. If a creature with deathtouch deals even 1 damage to another creature, that creature is destroyed—its toughness doesn’t matter. The same rule applies when deathtouch is granted to other sources, such as instant and sorcery spells that deal damage.
In play, deathtouch turns small creatures into potent threats and blockers. A 1/1 with deathtouch can trade with a giant attacker or blocker, making combat risky for your opponent. Because the ability cares about any amount of damage, it pairs well with effects that spread damage or grant deathtouch to spells. It can also fuel poison strategies, where combat damage from deathtouch creatures adds poison counters.
