He has hundreds of demons on the ship from all over the world. The Oni is a Japanese demon, and the skeleton demon is from freaking Tibet-that is half a world away from New York City and their usual stomping grounds in Asia. A part of me wants to also ask how they all fit on that boat, but apparently, Valentine stole an ocean liner or a cruise ship of some type.
It’s plausible that they can all fit perfectly.
However, I have a bigger question: How the fuck did that many demons converging from all over the world onto New York City was completely go undetected?
The Inquisitor would not know Valentine’s location if it wasn’t for that monitoring rune she put on the glass shard (and yes, we went over how that makes zero sense). How did no one in the Clave realize that Valentine had that many demons under his command? They don’t have a spy network, no way to detect a large amount of demonic activity? Valentine can’t be just using demons to do his bidding and no one in the Shadowworld knew about it. In a community like that, rumors had to be certainly flying; especially with Valentine being none too discrete about it.
Anyway, with The Clave’s great power, it seems to me that The Clave has no type of monitoring system. Any monitoring system worth their salt would have detected the large convergence of demons and triangulated Valentine’s position. Basically, if the Clave weren’t completely utter inept assholes they could have nipped Valentine in the bud by bringing the entire might of all the Shadowhunters around the world on them. Again:
IF YOU HAVE A BIG BATTLE WITH A BIG BAD, THEN IT’S ALL HANDS ON DECK PEOPLE!
But no once again, they just let Valentine do what he wants. Valentine and The Clave are just as bad as each other in my opinion. For example, how they just let Valentine disguised as war criminal Michael Wayland just waltz into the New York Insitute willy-nilly. Or how Valentine just chilled at Wayland’s estate for fucking years, and no one from The Clave went after him at all.
This is what happens when you dumb down everybody to make your protagonist look oh-so-clever. You get things that could have easily been nipped in the bud, escalating into this completely FUBAR situation.