It can do quite some cool stuff, can only recommend it :)
You can now get a picture LIVE from Mr Grass's lawn at watching-grass-grow.com with the command ::grass!
Plus you can now add (some) emoji from discordemoji.com with ::addemoji!
The epic commands you can use with Merlin:
Generate a provably random number.
Get the Klingon Word of the Day from Hol 'ampaS.
Search a Klingon (tlhIngan) dictionary, powered by the boQwI' database
Set a role to be mentionable, ping it, then unsets it again.
I think we all know what these are.
Merlin - a multipurpose bot that does Stuff™.