Transcript for Third Invictus games kicks off in Toronto

Finally tonight, invictus is Latin for unconquered. And tonight, it's also the very definition of the word comeback. Here's Marci Gonzalez. Reporter: A decade after his vehicle struck an ied in Iraq killing the soldier next to him and leaving him with a spinal cord injury, colonel Daniel Dudek, taking on this challenge, on the track and in the pool. It's more than an honor. It's part of his healing. He is one of the 550 injured military veteran athletes from 17 countries competing in this year's invictus games in Toronto. Now in his 26th year of military service, he is still on active duty. As he fights to take home a medal for team usa. I'm gonna beat my times, I'm gonna do what I can to win. Reporter: And in the owds, the creator of the invictus games, prince Harry. He is a warrior, I feel like he is one of us. Reporter: First lady Melania trump also there. But for Dudek, the focus is on the inspiration this competition can spark for wounded warriors. Heroes, just like him. Things like this hopefully can put a spotlight on something that I love and I want other disabled people to love. Reporter: Marci Gonzales, ABC news. Thanks to Marcy and the organizers of the invictus games, and all the incredible athletes. Thanks so much for watching. I'm Tom llamas in New York. "Gma" first thing in the

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