When I have Karlov of the Ghost Council and Soul Warden on the battlefield and I cast something like Lingering Souls, does Karlov get twice the +2/+2 counters since two spirits enter the battlefield or only once since I cast Lingering Souls once?

The same thing applies to beautiful cards such as Conqueror's Pledge - does Karlov get 6 times +2/+2 or only one?

When I have Karlov of the Ghost Council and Soul Warden on the battlefield and I cast something like Lingering Souls, does Karlov get two +1/+1 counters twice since two spirits enter the battlefield or only once since I cast Lingering Souls once?

The same thing applies to beautiful cards such as Conqueror's Pledge - does Karlov get two +1/+1 counters six times or only once?