Greek Gods
 

en toutw nika, Constantine's motto.

Does the omega at the end show that it is accusative or dative?

I thought the singular neuter is touto (with an omicron) and masculine is with an omega, am I right?

It's a dative, with an iota subscript (that little vertical line that hangs down like a . . . well, never mind).

I fell bad for touto. If you're going to be a neuter, at least you should be married first.