| Nominativ | antagonista, antagonistas, antagonista, antagonistas | antagonistae, antagonistae |
| Genitiv | antagonistae, antagonistai, antagonistae, antagonistai | antagonistum, antagonistarum, antagonistarum, antagonistum |
| Dativ | antagonistae, antagonistai, antagonistae, antagonistai | antagonistis, antagonistabus, antagonistis, antagonistabus |
| Akkusativ | antagonistam, antagonistam | antagonistas, antagonistas |
| Ablativ | antagonistad, antagonista, antagonistad, antagonista | antagonistis, antagonistabus, antagonistis, antagonistabus |
| Vokativ | antagonista, antagonista | antagonistae, antagonistae |
