PC states consisting of exotic combinations of quarks and gluons: ggg glueballs (oddballs),
q ̄ qg hybrid mesons and q ̄ qq ̄ q tetraquark systems. An odderon Regge trajectory is
computed for the J−− glueballs with intercept much smaller than the pomeron, explaining its
nonobservation. The lowest 1−+ hybrid-meson mass is found to be just above 2.2 GeV while
the lightest tetraquark state mass with these exotic quantum numbers is predicted around …