Who is correct (Magic the Gathering)?

Question

I have a Dimir House Guard (2/3) and a 1/1 creature.

My friend has a 3/2 and a 1/1 creature.

Dimir House Guard's ability is "Sacrifice a creature: Regenerate Dimir House Guard.".

Rule Book says, "Once Blockers have been assigned to Attackers, Combat Damage goes on the stack and players are allowed to play Instants and Activated Abilities".

My opponent attacks with his 3/2 and his 1/1.

I assign Dimir House Guard to block the 3/2 and my 1/1 to block his 1/1.

Now that blockers have been assigned and Combat Damage is on the stack, I choose to play Dimir House Guard's ability ("Sacrifice a creature: Regenerate Dimir House Guard."). I sacrifice my 1/1 that was assigned to block his 1/1.

I explained to my friend that (rule 310.2c) because his 1/1 was assigned a blocker and that Combat Damage is on the stack, when the Combat Damage resolves, it will go to look for the creature that his 1/1 was blocked by, it will not find it, and thus his 1/1 will not deal damage.

Am I right?

Answer 1

You are correct, sir.  Although I always believed that there was a transition from the block step to the damage phase instead of there being a stack, the end result is the same.

Answer 2

Up, you're right.

Nice use of the stack, by the way.

Answer 3

That is correct, I have gone through numerous times with many players.