Whenever Kazuul Warlord or another Ally enters the battlefield under your control, you may put a +1/+1 counter on each Ally creature you control.
This ability triggers on this creature entering the battlefield, so it will enter the battlefield with its unmodified power and toughness, and then receive a +1/+1 counter a short time later. It does not enter the battlefield with the +1/+1 counter already on it.
Unlike other Allies with similar abilities, Kazuul Warlord’s ability lets you put +1/+1 counters on all your Ally creatures, not just itself.