Mr Odinga said his legal team had concrete evidence that would lead to the nullification of the presidential election results.
Speaking figuratively about a hunter spearing an antelope, Mr Odinga said the hunted animal will eventually die.
"As I am speaking to you, I can feel the impact of unleashing the spear on the antelope in my arm. With a spear deep in its body, it will not survive," he said.
"I don't want to go into the details of the evidence we filed, that is before the judges now."
He made the remarks after a surprise appearance at the swearing-in of Kisumu Governor Anyang' Nyong'o.
Karua in Homa Bay
His running mate in the August 9 polls, Martha Karua, was in Homa Bay County to witness the swearing-in of Gladys Wanga as the first woman governor in the Nyanza region.
Mr Odinga noted that 24 county bosses were elected under Azimio la Umoja One Kenya and the party will control the Council of Governors.
"Today is a proud day for us as the Azimio family,” he said.
He went on: "It is not an impression of control, but we want to prove governance at the level of counties. We want to make devolution work for the people of our country."
But he noted that some people don’t believe in devolution, and many resisted it when Kenyans were fighting for a new Constitution.
"Things have not worked properly because those who are charged with the responsibility of implementing it don't themselves believe in it," he said.
He argued that devolution can revolutionise governance in the country.
"It can help to realise the Azimio vision of empowering our people, fighting poverty and ensuring that people participate in governance," he said.
The biggest obstacle to realising the goals of devolution is corruption, he added.
“The elephant in the country today is corruption. Unless you address the issue of corruption, it does not matter how much money you get or borrow. If you don’t put it to good use, it causes poverty among our people,” he said.
He said leaders must kill the dragon of corruption if Kenya is to prosper.