Error-prone polymerase lacking a proofreading 3'-5' exonuclease which catalyzes the gap-filling reaction during the DNA repair process (By similarity). Specifically binds intermediates in the single-nucleotide base-excision repair process (By similarity). Also catalyzes DNA polymerization with low nucleotide-insertion fidelity (By similarity). Probably acts as a strategic DNA mutase, which gives rise to a rapid emergence of variants (By similarity). Generates mismatched G-G pairs, in that case, the polymerase first binds the deoxynucleotide followed by mismatch formation (By similarity). Together with the viral DNA ligase, fills the single nucleotide gaps generated by the AP endonuclease (Probable). Binds DNA with high affinity via the helix alphaE (By similarity). a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1) In the presence of magnesium, pol X shows a strong preference for the ssDNA gaps having one and two nucleotides. Found in association with viral nucleoid. Small DNA polymerase formed from only a palm and a C-terminal subdomain (By similarity). The total DNA-binding site of pol X is composed of two DNA-binding subsites (By similarity). Consistent with its intracellular location, ASFV encodes its own replicative DNA polymerase and three base excision repair enzymes: a class II AP endonuclease, the repair polymerase Pol X, and an ATP-dependent DNA ligase. Belongs to the DNA polymerase type-X family.