This paper presents a classification of unconventional quasiparticles in conventional crystals, beyond the well-known Dirac and Weyl fermions. The authors identify and classify various types of fermionic excitations in solid-state systems, which are protected by crystal symmetries and spin-orbit coupling. They exhaustively analyze 3-, 6-, and 8-band crossings in solid-state systems, considering the effects of space group symmetries, time-reversal symmetry, and spin-orbit coupling. The classification reveals several distinct types of fermions, characterized by their degeneracies at high-symmetry points, lines, and surfaces in the Brillouin zone. The study identifies three-fold, six-fold, and eight-fold degeneracies, which arise from different combinations of symmetries. For example, three-fold degeneracies are associated with half-integer angular momentum fermions, while six-fold degeneracies can result from the combination of time-reversal and inversion symmetries. The authors also show that these fermions can exhibit unique topological properties, such as non-trivial Berry curvature and the presence of Fermi arcs, which are typically associated with Weyl and Dirac fermions. The paper also discusses the experimental signatures of these fermions, including their effects on transport properties, surface states, and ARPES measurements. The authors propose several candidate materials that host these exotic fermions near the Fermi level, such as Pd3Bi2S2, Ag3Se2Au, Ba4Bi3, and others. These materials are analyzed using density-functional theory and other computational methods to confirm the existence of the desired band crossings. The study highlights the importance of non-symmorphic crystal symmetries in stabilizing these fermions, as they allow spin-1/2 electrons to transform under integer spin representations of the rotation group. The authors also discuss the implications of these findings for the broader field of condensed matter physics, suggesting that these new fermions could lead to novel surface states, magnetotransport properties, and topological phases. The paper concludes with an outlook on future research directions, including the exploration of magnetic space groups and the potential for new topological phases.This paper presents a classification of unconventional quasiparticles in conventional crystals, beyond the well-known Dirac and Weyl fermions. The authors identify and classify various types of fermionic excitations in solid-state systems, which are protected by crystal symmetries and spin-orbit coupling. They exhaustively analyze 3-, 6-, and 8-band crossings in solid-state systems, considering the effects of space group symmetries, time-reversal symmetry, and spin-orbit coupling. The classification reveals several distinct types of fermions, characterized by their degeneracies at high-symmetry points, lines, and surfaces in the Brillouin zone. The study identifies three-fold, six-fold, and eight-fold degeneracies, which arise from different combinations of symmetries. For example, three-fold degeneracies are associated with half-integer angular momentum fermions, while six-fold degeneracies can result from the combination of time-reversal and inversion symmetries. The authors also show that these fermions can exhibit unique topological properties, such as non-trivial Berry curvature and the presence of Fermi arcs, which are typically associated with Weyl and Dirac fermions. The paper also discusses the experimental signatures of these fermions, including their effects on transport properties, surface states, and ARPES measurements. The authors propose several candidate materials that host these exotic fermions near the Fermi level, such as Pd3Bi2S2, Ag3Se2Au, Ba4Bi3, and others. These materials are analyzed using density-functional theory and other computational methods to confirm the existence of the desired band crossings. The study highlights the importance of non-symmorphic crystal symmetries in stabilizing these fermions, as they allow spin-1/2 electrons to transform under integer spin representations of the rotation group. The authors also discuss the implications of these findings for the broader field of condensed matter physics, suggesting that these new fermions could lead to novel surface states, magnetotransport properties, and topological phases. The paper concludes with an outlook on future research directions, including the exploration of magnetic space groups and the potential for new topological phases.