You can see the Dwarf as a very powerful and versatile guitar multieffect : hundreds of free plugins (and some plugins cost around 20 euros ) can be downloaded to the device and patched together in a flexible way.
You can see it as modular synth (not specialist but all sorts of vco, filters, adsr, vca, midi & cv utilities...are available) as well as an audio2pitch plugin, so that it's possible to plug either a keyboard or a guitar (mono synth).
(just browse the mod audio plugin store to get an idea).
Minor drawback : no control port input, so one has to use midi expr pedal or footswitch if needed.
But in my opinion the most specific aspect of this device is that it is completely opened. It is actually a computer and an audio interface packed in a stomp box, and all that is needed to build new LV2 plugins (standard similar to VST) for the dwarf is available online, so that the library is expandable not only by MOD audio dev team, but also anyone who has the skills.
(this makes dwarf different from zoia for example, even if they are similar in terms of patching flexibility).
Finally, the MOD team is really enthousiast and reactive on the forum. They are quick to provide any help (as well as the community), and when users ask for new features, at least they file the requests, but occasionally they publish some experimental (may be unstable) way to hack the device , while waiting to integrate it into a stable release. (ex : some users asked if the dwarf could act as an audio interface ; they answered: well , it could, it's not official, but try this).