Kagome-based magnetic metals are recognized as exemplary systems for the study of quantum materials, offering a distinctive framework to investigate the interrelation of topologically nontrivial electronic structures, geometrically frustrated magnetic moments ($f\approx 7$), and strongly correlated electron phenomena. The growth and detailed analysis of the $4d$ kagome metal $\mathrm{TbN}{\mathrm{b}}_6\mathrm{S}{\mathrm{n}}_6$ are reported, in which a kagome network of Nb atoms is integrated with a triangularly frustrated arrangement of localized ${\mathrm{Tb}}^{3+}$ moments. High-quality crystals are found to adopt the centrosymmetric $\mathrm{HfF}{\mathrm{e}}_6\mathrm{G}{\mathrm{e}}_6$-type structure ($P6$/mmm), with lattice constants precisely refined to $a=b=5.75791\AA$ and $c=9.55520\AA$. Striking uniaxial anisotropy is revealed by magnetization measurements, with the magnetic susceptibility along the $c$ direction exceeding the in-plane susceptibility by nearly 50-fold just above 3 K, indicating a strong out-of-plane alignment preference of the ${\mathrm{Tb}}^{3+}$ $4f$ moments. Two successive magnetic transitions are observed at zero magnetic field at $T_{\mathrm{N}}=2.91$ K and $T_2=2.32$ K. When a magnetic field is applied along the $c$ direction, four distinct metamagnetic transitions are observed at low temperatures, culminating in a fully polarized moment of 8.24 ${\mu }_{\mathrm{B}}$/Tb ion at 2 K above 3.6 T, as evidenced by both magnetization and resistivity measurements. A positive, nonsaturating magnetoresistance and a nonlinear Hall effect are exhibited by the compound across the full temperature range studied. First-principles calculations show that the Fermi level is dominated by Nb $4d$ orbitals, which generate kagome-derived bands featuring Dirac crossings and Van Hove singularities indicative of nontrivial topology. The potential of the $R\mathrm{N}{\mathrm{b}}_6\mathrm{S}{\mathrm{n}}_6$ family as a versatile platform for realizing emergent quantum states is highlighted by the combination of tunable magnetic anisotropy, complex spin textures, and multiband conduction.

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• Magnetic anisotropy
• Metamagnetism
• Topological phases of matter
• Kagome lattice
• Rare-earth ions
• Strongly correlated systems
• Magnetization measurements