Drivnod, Carnage Dominus

If a creature dying at the same time that another permanent you control leaves the battlefield causes a triggered ability of that permanent to trigger, that ability triggers an additional time.

If you somehow control two Drivnods, a creature dying causes abilities to trigger three times, not four. A third Drivnod causes abilities to trigger four times, a fourth causes abilities to trigger five times, and so on. This also means that if you control Drivnod and cast a second one, an ability that triggers when it dies due to the "legend rule" triggers three times.

The trigger event doesn't have to specifically refer to "creatures." In these cases, the trigger event may also refer to something being "put into a graveyard from the battlefield." For example, an ability that triggers "whenever an artifact is put into a graveyard from the battlefield" would trigger twice if an artifact creature dies while Drivnod, Carnage Dominus is on the battlefield.