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I was playing my son using a green deck. I played a Pelakka Wurm which has trample. He played an Eldrazi with deathtouch. He is a firm believer as soon as the attackers and blockers are announced, the deathtouch would kill the Wurm. I tried to get him to understand it would be taken care of in the damage phase and the Trample would in fact still do its damage.
Now, I know that Trample damage will take affect on the defending player only after it does lethal dmg to the blocking creature. So, I announce the attackers and he announces the defenders. The issue I have is, would my dmg take affect before his deathtouch does. I believe my dmg is resolved first, activating the trample. His dmg is activated second, satisfying the rules for deathtouch to work. That card would destroy the Wurm, but the Wurm would complete the Trample before.