Possible Clues:

• Major river of East Africa
• Maze biz (anag.); African river
• River flowing into Indian Ocean north-east of Beira in Mozambique
• African river, flows into the Indian Ocean
• River forming, in part, the border between Zambia and Zimbabwe
• River in Africa
• River with Victoria Falls
• River running over the Victoria Falls
• River through Victoria Falls
• Zulus, one crossing briefly Orange River