This question already has an answer here:
Scenario: I have Thelon of Havenwood and a Thallid with 9 spore counters. My opponent attacks with a 10/10 and I block with my Thallid (also 10/10). I want to block and kill his 10/10, and then create 3 saprolings before Thallid hits the graveyard.
My assumption is that during Combat Damage Step I assign 10 points of damage to my opponents creature, as his creature assigns 10 to my Thallid. Then during the End of Combat Step I can activate it's ability to create saprolings because damage was already assigned.
Am I correct?