Necratog with Wonder in GY Question

[Cavius The Great]

If I have a Necratog in play with 10 creatures in my graveyard and one of them being a Wonder, Could I attack with a flying Necratog then remove the creatures in my yard for the win? Or will my Necratog lose flying during the process if i remove the Wonder? I'm assuming that you can attack with a flying Necratog and after no blockers are declared, it gets through, then before damage goes on the stack I could remove the critters in my yard while my unblocked Necratog remains unblockable. I'm not sure though and that's why I'm asking this question. Any help would be greatly appreciated. Thanks ahead of time.

[Komatteru]

Yeah, you can remove the Wonder from the yard to pump the Tog after blockers are declared. Combat goes

Beginning of combat
[chance for effects]
Declare Attackers
[chance for effects]
Declare Blockers
[chance for effects]
Combat damage
[chance for effects]
End of combat

Blockers can only be declared at the declare blockers stage.  If your opponent has no flying creatures, then he can't block Necratog.  Sure, once you remove Wonder, Necratog doesn't fly any more, but there's no opportunity to block now, so it doesn't matter.

Chimeric Sphere has become better since it was printed because of this revised combat plan.  You can make it a 2/1 flyer, attack, and then make it a 3/2 after that.

EDIT:
Also, note that if you were on defense, you could do this if you have Wonder in the yard (say it's your only creature in there): block Phantom Monster with Necratog, then remove the Wonder to pump Necratog and have it survive combat.  A blocker only needs to have flying when it is declared as a blocker to block a flying creature.  If it loses flying after the blockers have been declared, the attacking creature does not become "unblocked."  Similarly, giving a creature protection from the appropriate color after the blocker has been declared does not make the blocking assignment fail (the damage prevention effect of protection will apply, but nothing else).  Triggered abilties such as flanking and bushido must be on the creature before the blocker is declared.  Giving a creature bushido after it has been blocked will not give it the bonus.

[DMMBY]

Slight Nitpick
your forgot
Combat Damage
Assignment of First Strike Combat Damage (goes on stack)
[First strike damage]
Assignment of Normal Combat Damage (goes on stack)
[Normal combat damage]

that can matter when it comes to playing spells

[Godder]

First Strike Damage only gets applied if there's a creature with First Strike attacking or blocking. In the Tog case, there probably isn't, so it won't be applied.