Old Blood Noise Endeavors Dark Star

It goes without saying that this is not a generic reverb. If you are looking for rooms, halls, springs etc., search elsewhere.

As a creative and intuitive tool it does do a good job. However, some of its parameters do not work as one would expect. For example, the mix (wet/dry) knob does not really adjust the volume of the dry signal until up around 95% where, as expected, you get only the reverb. So, you cannot really control the volume of the dry signal, it is essentially only on or off.
Also, the octave up sounds very unnatural, mainly because it creates an almost tremolo effect.

Overall, the pedal opens a lot of sonic possibilities, but not without some issues.

Ambient music oriented "pad reverb" with three modes for colouring the sound, plus a great feeling for live interaction with the controls, all in all this pedal is pure magic. If you like long reverbs, from super clean to dirty to self oscillating, or wish to pitch shift the reverb tone, this is the pedal you look for. Great for guitars and synthesizers!
The solid build, the great sound response, will make you sure this pedal is the perfect choice. It's great at the beginning of a pedal chain, to create long swells (or infinite ones), but even further in the chain it gives amazing results for the clarity of the sound.

I see non cons, apart that a stereo version of this pedal would be an instant buy.

The Dark Star adds a really nice layer of atmospheric noise to what you're playing, which for me is useful in the black metal project I'm using it for. If you're looking for a more general reverb this probably isn't a good option for you, I also have a Hall of Fame 2 and find this much better for general reverb. However, what the Dark Star specialises in, it does well.

The build in general is really good, and I love the gfx on the case. The buttons do feel a little cheap compared to the rest of the build, but work fine. Overall a nice pedal, but niche in it's use.

The pedal works best on slower, more ambient pieces and adds a dark flavour to melodies. I bought the pedal mainly for the bit crusher mode for Alt-rocky riffs and the other modes for clean melodic stuff. My biggest problem with the pedal is that the sounds aren't clean and it can be tricky to get the right settings. But when you do find the right settings, it can give a somber melody a sense of impending doom or create absolute chaos. You can also hook it up to an expression pedal and have a chord ringing out in the background, which can help when improvising. The Dark Star takes time to get used to and when you do, the wide array of sounds can add a texture to your playing that can't be achieved otherwise.

I've been using the pedal for quite some time now and it was exactly what I hoped for. I've been using with guitar and analog synths and it reacts very well with both.
If you already have a reverb and you want a more experimental pedal to create huge ambient textures, add more darkness to your clean guitar sound, or maybe awaken some great old one sleeping under you city, then this is it!

pros:
great dark sound
lots of parameters to tinker with
ideal for experimentation
its looks are awesome

cons:
it feels a bit fragile, but I could be wrong

Although I returned it, I'm still giving this pedal 4 stars in total just because of its unique sound. On the downside, the overall sound quality is a bit too Lo-Fi for my taste, but actual reason I returned it is that the pedal is noisy - it raised the noise floor of my signal chain significantly which to me is a deal breaker.

Pros: truly unique sound unlike any other reverb, great for experimental music, dark ambient, drone.

Cons: kind of Lo-Fi, and too noisy.

So if you are into experimental music but don't really care about high fidelity, go ahead and get it, it will be very useful to you.