While the guitar melody in "Overworld" is nice, I felt the song would've been improved if you had developed the melody a bit more beyond simple modal changes. I enjoyed the bass melody in the middle transition.The bass and synth arpeggios are nice elements.
I felt like the chord progressions and its rhythm in "Tension" could provide the basis for a really cool song, but IMO it could use some percussive and/or melodic elements.
"Boss" had a nice rhythm and the echo on the high pitched pluck was a cool effect.