Dirgur Nemesis

[AwaySinceMirage]

{Dirgur Nemesis} has morph (megamorph actually) and defender.
Making sure, this can be declared an attacker while face down, then can be turned face up and still be attacking despite defender?

[Kaylesh]

{Dirgur Nemesis} has morph (megamorph actually) and defender.
Making sure, this can be declared an attacker while face down, then can be turned face up and still be attacking despite defender?

From prerelease notes:
If an attacking face-down Dirgur Nemesis is turned face up, it will continue to be attacking even though it will have defender.

In general, if a creature with defender is put on the field attacking by an effect, it still attacks. This is something that IMHO should be worked on in the CR though. The CR are not quotable on this.

[AwaySinceMirage]

Duh I should read those prerelease notes. I only read the gatherer that had no rulings. Thank you Kaylesh!

[Kaylesh]

Duh I should read those prerelease notes. I only read the gatherer that had no rulings. Thank you Kaylesh!

NP man.

[Prplprince]

It's has the same interaction if you cheat in a  {Slumbering Dragon} With  {Kaalia of the Vast}. Although he can't attack Kaalia lets him by pass the rule because it enters the battlefield tapped attacking. Same thing would happen if you cheated in a  {Dragon Egg} (although I don't know why but eh). It will be attacking even though it had defender

[Munchlax]

In other words, all defender keeps you from doing is declaring it as an attacker

[Pi]

These are a part of the declare attackers step.
508.1c: The active player checks each creature he or she controls to see whether it's affected by any restrictions (effects that say a creature can't attack, or that it can't attack unless some condition is met). If any restrictions are being disobeyed, the declaration of attackers is illegal.
Example: A player controls two creatures, each with a restriction that states "[This creature] can't attack alone." It's legal to declare both as attackers.

508.3: Third, the active player gets priority. Players may cast spells and activate abilities.

So yes you can declare as an attacker, checks for defender, then you have priority to morph.