Okay yeah the story of Splatoon Raiders is kinda scummy when you read into it but I don't think it's wholly colonialism, but rather just good old piracy on Deep Cut's part
Let's take a look at the definition of coloialism
And Deep Cut is stealing treasure from the Salmonids but I wouldn't say it's a "resource", not to mention it's only these 4 bozos doing it and not a whole nation or whatever. They're not forcing anything onto the Salmonids either(besides maybe an early grave-) again they're just stealing the shiny shit for money
So yeah I'm pretty sure doing 1 out of the 4 things doesn't make it colonialism. Still super sucky but I think I've made my point



















