DeathtouchDeathtouch is a static ability.
A creature with toughness greater than 0 that’s been dealt damage by a source with deathtouch since the last time state-based actions were checked is destroyed as a state-based action. See rule 704.
Any nonzero amount of combat damage assigned to a creature by a source with deathtouch is considered to be lethal damage for the purposes of determining if excess damage is being dealt.
The deathtouch rules function no matter what zone an object with deathtouch deals damage from.
If an object is no longer in the zone it’s expected to be in as an effect causes it to deal damage, its last known information is used to determine whether it had deathtouch.
Multiple instances of deathtouch on the same object are redundant. (CR 702.2)
Whenever this creature deals combat damage to a player, they get four
rad countersRad counters are a kind of counter a player can have (see rule 122, “Counters”). There is an inherent triggered ability associated with rad counters. This ability has no source and is controlled by the active player. This is an exception to rule 113.8. The full text of this ability is “At the beginning of each player’s precombat main phase, if that player has one or more rad counters, that player mills a number of cards equal to the number of rad counters they have. For each nonland card milled this way, that player loses 1 life and removes one rad counter from themselves.” (CR 728.1).
Whenever a player mills a nonland card, you gain 1 life.