One Piece Episode 374

He's goin by the fact that Oz was model 900 but, if you noticed there were zombies with numbers in the 1100s so there's actually more than 1k but can't be sure consider that some were defeated prior to this arc by the ppl looking for their shadows in the forest. Oz was a special zombie meant for an extremely powerful shadow.

euhm yeah they did, remember when moria went to the mario of Odz and he was all proud of making his 900th zombie, Luffy's shadow was the 900th shadow to be placed in a mario

also wouldn't it have been funny if Moria farted out all of the shadows :P

another thing is that he has 900 zombies that have a shadow, and then he got the 100 more from luffy

there may have been more then 900 zombies some may not have been numbered odz just happens to be 900 he was 900 long before alot of the zombies where made.

He's saying there's only 900 because that's Oarz's (Odz) number.

But just because he's the 900th marimo doesn't mean there weren't more made before he had Luffy's shadow put in him.

just to show off exactly how badass you can be to not even flinch at the prospect of dying in the next couple of seconds. And also I always wondered why it took Luffy so much to finally combine Gear Second and Gear Third... though he didn't actually use any techniques, he just headbutted Moria twice after he combined the gears.