Kari5

Ninja Collection is a spin-off of the Yamishibai franchise, and is similar in almost every way except the story endings. It has short form, episodic horror stories, like spooky urban legends or campfire stories. It falls short of being actually scary, or even suspenful in many cases, however I don't feel like it deserves the hate it, and the rest of the Yamishibai franchise, gets.

Animation

First things first, we need to talk about the animation. Its always the first thing people react to, and always negatively. To explain, its an old form of street story-telling in Japan, where images are pulled out of a wooden display device. So, basically an image to go along with the story. They re-create this in anime form by using narration, and limited movement. Entire frames are moved, or occassionally a piece of something in a scene, but it still moves like a piece of paper.

If you don't like this kind of animation DO NOT WATCH THIS. It drives some people up the wall. If you go in knowing about the animation/history, its much easier to appreciate the style, but its not for everyone. You're basically in for narration over creepy images.

Stories

Like in the original franchise, these are all stand-alone "spooky" tales, but with a small twist. Instead of creepy endings, most of these end with a ninja dropping by to save the day (killing demon, ghost, etc.). This makes them less spooky than before because the main character is often saved, and the bad thing vanquished. Before it was an open ending and often you assume someone ends up dead. They also have less of an 'urban folk tale' vibe and more of a modern demon killing vibe, which hurts the suspense of the stories.
The stories themselves are okay, but not amazing. Might be fine around a campfire or something, but not super suspenseful as an anime. While I assume they're not designed for a young audience, it might work best for kids because its spooky like Goosebumps (as an adult, not much, but scary to kids).

Characters

Not much to say, they're usually pretty generic people just used to tell the story. We don't really get a chance to care much about them in the short episodes, and many don't even get names. The only re-occuring characters are the ninjas, one per episode for a few seconds. We don't know anything about them, and they are not really interesting in any way.

Overall

Its not a total waste of time if you like spooky/suspenseful things, the episodes are only 4 minutes each. I'd still recommend it to peole who like this kind of stuff, though the Yamishibai stuff is better. However, if you can't get over the simplistic animation, you will HATE this, hands down. I think these types of shows have potential, but after 7+ seasons they are getting a bit predictable and I'm losing more interest every year.