Plays an important role in rhoptry physiology and thus is essential for merozoite invasion of host erythrocytes. Localizes below the host erythrocyte cell membrane (PubMed:19777263). Localizes to the cell membrane of merozoites (PubMed:19777263). In merozoites, localizes to the cytosolic face of the rhoptry bulb membrane (PubMed:35140336). During parasite asexual blood stages, expressed in trophozoites and at the schizont stage (at protein level). The number of deca-peptide repeats in the C-terminus varies across P.falciparum strains (PubMed:19777263). Strain 3D7 has 12 copies; Dd2 has 14 copies; Hondura-1, FCC1, FCC2, and T996 have 17 copies; and strain D10 and FCR3 have 19 copies (PubMed:19777263). Impairs merozoite invasion of host erythrocytes at, or prior to, the formation of the tight junction (PubMed:35140336). Merozoite development and egress following schizont rupture are not affected (PubMed:35140336). Inhibits rhoptry bulb RAP1 processing but not secretion of rhoptry neck proteins RH4 and RON4 (PubMed:35140336). Causes defects in rhoptry morphology which are narrower and more elongated (PubMed:35140336). No defect in microneme secretion (PubMed:35140336). Antibodies against CERLI2 severely reduces parasitemia, suggesting that CERLI2 is a potential vaccine candidate.