LifelinkLifelink is a static ability.
Damage dealt by a source with lifelink causes that source’s controller, or its owner if it has no controller, to gain that much life (in addition to any other results that damage causes). See rule 120.3.
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 lifelink.
The lifelink rules function no matter what zone an object with lifelink deals damage from.
If multiple sources with lifelink deal damage at the same time, they cause separate life gain events (see rules 119.9–10).
Multiple instances of lifelink on the same object are redundant. (CR 702.15)
ExploitExploit is a triggered ability. “Exploit” means “When this creature enters, you may sacrifice a creature.”
A creature with exploit “exploits a creature” when the controller of the exploit ability sacrifices a creature as that ability resolves. (CR 702.110) (When this creature enters, you may
sacrificeTo sacrifice a permanent, its controller moves it from the battlefield directly to its owner’s graveyard. A player can’t sacrifice something that isn’t a permanent, or something that’s a permanent they don’t control. Sacrificing a permanent doesn’t destroy it, so regeneration or other effects that replace destruction can’t affect this action. (CR 701.21) a creature.)
Other legendary creatures you control have
exploitExploit is a triggered ability. “Exploit” means “When this creature enters, you may sacrifice a creature.”
A creature with exploit “exploits a creature” when the controller of the exploit ability sacrifices a creature as that ability resolves. (CR 702.110).
Whenever a creature you control exploits a creature, put a +1/+1
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on each creature you control.