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