Commander damage

[Lunis22]

I have constructed a dragon deck with scion of the it dragon as the commander. My question is using his ability does the damage done when he is copying another dragon count towards the 21 commander damage limit? Commander rule states that even a copy of another creature is still a commander but is it still considered the same commander?

[Double-O-Scotch]

Scion becomes a copy, but it's still the same permanent. It will count towards GD

[Giggle the Draco Genius]

The copy will not actually be dealing commander damage. 

The commander trait itself is not a copiable charateristic and as such it will not count towards the commander damage.

Taken from the commander rules website. http://mtgcommander.net/rules.php

9. Being a Commander is not a characteristic[MTG CR109.3], it is a property of the card. As such, "Commander-ness" cannot be copied or overwritten by continuous effects, and does not change with control of the card.
Examples: A Body Double copying a Commander in a graveyard is not a Commander. A Commander which is affected by Cytoshape, or is face down, is still a Commander.

[Nymuera]

Right, but I believe he is talking about {Scion of the Ur-Dragon}. In that case the commander itself copies another creature and retains the commander property.

[Giggle the Draco Genius]

Right, but I believe he is talking about {Scion of the Ur-Dragon}. In that case the commander itself copies another creature and retains the commander property.

My reading comprehension seems to have degraded recently, you are correct, I thought it was a commander deck with Scion in it, not as the commander.  Sorry about that.  The rulings that I linked help, but not for this situation.

[Pleeb]

903.14a: A player that's been dealt 21 or more combat damage by the same commander over the course of the game loses the game. (This is a state-based action. See rule 704.)

Please keep in mind I don't play commander. When scion uses his ability, he will still be the same permanent, will keep his counters and enchantments, assigned damage etc. I'm interpreting the above rule as all damage dealt by him in whatever copied form will count as the same permanent, and thus the same commander.

[MuggyWuggy]

 {Skithiryx, the Blight Dragon}
{Moltensteel Dragon}

[particle]

{Skithiryx, the Blight Dragon}
{Moltensteel Dragon}

yea ive lost to the above combo in edh a few times. infect is the only wincon i dont like in edh. at least make it 15 or 20 poison.

[Remillo]

Biggest thing to take away from this is that 'Commander-ness' is a trait of the card itself.  No matter what happens to that card, it's still the commander.  Turn it Face-down?  It's a 2/2 dealing commander damage.  Copy another permanent?  Still the commander.  It's not uncommon for Scion to One-Shot people by transforming in to {Moltensteel Dragon} and pumping up to 21 power.