From the recording Backing and Jam Tracks for Bass Guitar Vol. 4
C# Minor is the most underrated keys to play in on the bass guitar. Try using the open E string to get the b3rd when adding fills or soloing. Albert King's riff on "Born Under A Bad Sign" does this very well. Try transcribing that bass line and integrating those notes into your bass line and soloing. 108 BPM.
Chords:
||: C#min | | | :||