Let’s say one creature has died this turn. I have Kaervek, the Spiteful on the battlefield, and then I flash in Liliana's Standard Bearer. This card has an enters-the-battlefield trigger which says "draw X cards where X is the number of creatures that died this turn".
Obviously the Standard Bearer is going to die immediately to Kaervek’s static ability. When the enters-the-battlefield trigger resolves, does it count the Standard Bearer as a creature that died this turn?