Does your commander still count as being your commander if it is turned face down?
For example, I have my commander on the battlefield and my opponent plays Ixidron. Ixidron then turns my commander face down.
Creatures turned face down by Ixidron are 2/2 creatures with no text, no name, no subtypes, no expansion symbol, and no mana cost.
Will my face down commander still:
- deal commander damage?
- enable "Lieutenant" abilities?
Is the result different if my commander is turned face down by another means?