Atabeyarchaeia and Freyarchaeia represent two distinct lineages within the Asgard superphylum, expanding our understanding of archaeal diversity and metabolic capabilities. Genomic analyses reveal that Atabeyarchaeia are likely non-methanogenic acetogenic chemoheterotrophs with potential for lithoautotrophic growth using H2 as an electron donor. They possess pathways for degrading amino acids and other carbon compounds, including the ability to metabolize C1, C3, and C5 compounds, which is uncommon among Asgard archaea. Freyarchaeia, originally described as a separate lineage, shares some metabolic features with Atabeyarchaeia but exhibits distinct characteristics. Both groups are positioned within the Asgard clade, with phylogenetic analyses using multiple marker gene sets (including 47 archaeal clusters of orthologous genes, 15 ribosomal protein genes, and the 16S rRNA gene) consistently placing Atabeyarchaeia as a sister group to Freyarchaeia. Despite sharing only 40-45% average amino acid identity with other Asgard genomes, both lineages are classified within the Asgardarchaeota phylum, adhering to the Genome Taxonomy Database (GTDB) standards. The proposed classification establishes Atabeyarchaeum as the type genus for the family Atabeyarchaeaceae, order Atabeyarchaeales, and class Atabeyarchaeia, while maintaining Freyarchaeia as a distinct lineage within the same phylum. This research highlights the metabolic diversity within the Asgard superphylum and provides insights into the potential roles of these archaea in carbon cycling and their interactions with other microbial communities in various ecosystems.