| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 26. N M Ostensen vs A Domalchuk-Jonasson |
| 0-1 | 51 | 2023 | Kragero Resort Chess | D02 Queen's Pawn Game |
| 27. N M Ostensen vs R Skytte |
| 1-0 | 36 | 2023 | Norway Chess Open Masters | A06 Reti Opening |
| 28. N M Ostensen vs P Carroll |
| 1-0 | 29 | 2023 | Norway Chess Open Masters | A27 English, Three Knights System |
| 29. Shri B Savitha vs N M Ostensen |
| ½-½ | 72 | 2023 | Norway Chess Open Masters | C65 Ruy Lopez, Berlin Defense |
| 30. S Zylka vs N M Ostensen |
| 1-0 | 77 | 2023 | Norway Chess Open Masters | E69 King's Indian, Fianchetto, Classical Main line |
| 31. N M Ostensen vs H Z Zheng |
| 1-0 | 68 | 2023 | Norway Chess Open Masters | C84 Ruy Lopez, Closed |
| 32. N M Ostensen vs V B Medhus |
| 1-0 | 28 | 2023 | Norway Chess Open Masters | A35 English, Symmetrical |
| 33. J Zhu vs N M Ostensen |
| 1-0 | 38 | 2024 | Semana Santa Open | B30 Sicilian |
| 34. D Ser vs N M Ostensen |
| ½-½ | 34 | 2024 | European Youth Championship U16 | A45 Queen's Pawn Game |
| 35. R Arnold vs N M Ostensen |
| ½-½ | 91 | 2024 | European Youth Championship U16 | B30 Sicilian |
| 36. N M Ostensen vs A Salonen |
| ½-½ | 53 | 2024 | European Youth Championship U16 | A04 Reti Opening |
| 37. I Musial vs N M Ostensen |
| 0-1 | 33 | 2024 | European Youth Championship U16 | B32 Sicilian |
| 38. N M Ostensen vs R Pashikyan |
| 0-1 | 46 | 2024 | European Youth Championship U16 | E67 King's Indian, Fianchetto |
| 39. D Kassios vs N M Ostensen |
| ½-½ | 48 | 2024 | European Youth Championship U16 | B30 Sicilian |
| 40. N M Ostensen vs M Csernyik |
| 1-0 | 60 | 2024 | European Youth Championship U16 | A16 English |
| 41. I Hajialiyev vs N M Ostensen |
| 0-1 | 68 | 2024 | European Youth Championship U16 | B22 Sicilian, Alapin |
| 42. G N Gopal vs N M Ostensen |
| 1-0 | 38 | 2025 | Fagernes GM Open | C90 Ruy Lopez, Closed |
| 43. N M Ostensen vs D Arvola |
| 1-0 | 38 | 2025 | Fagernes GM Open | E94 King's Indian, Orthodox |
| 44. Y Zhou vs N M Ostensen |
| 1-0 | 43 | 2025 | Fagernes GM Open | C55 Two Knights Defense |
| 45. N M Ostensen vs L Khoo-Thwe |
| 0-1 | 59 | 2025 | Fagernes GM Open | C97 Ruy Lopez, Closed, Chigorin |
| 46. L T Haugen vs N M Ostensen |
| 0-1 | 49 | 2025 | Fagernes GM Open | C55 Two Knights Defense |
| 47. N M Ostensen vs S Torfoss |
| 1-0 | 82 | 2025 | Fagernes GM Open | A28 English |
| 48. I V Brattgjerd vs N M Ostensen |
| 0-1 | 37 | 2025 | Fagernes GM Open | C63 Ruy Lopez, Schliemann Defense |
| 49. N M Ostensen vs M Vestby-Ellingsen |
| ½-½ | 27 | 2025 | Fagernes GM Open | C77 Ruy Lopez |
| 50. T Hillarp Persson vs N M Ostensen |
| 1-0 | 34 | 2025 | Fagernes GM Open | E92 King's Indian |
Kibitzing
