ɪf ˌɛni tɹæsˈʊɹ ɪnðə ɡɹˈuːp klˈeɪmd ðæt hiː hæd kəmplˈiːɾᵻd ɐ dˈɪfɪkəlt ænd dˈeɪndʒɚɹəs tʃˈælɪndʒ ðæt ʃˌʊd nˌɑːt biː ɐtˈɛmptᵻd ʌnˈeɪdᵻd, hiː hædtə pɹˈuːv hɪz klˈeɪmz baɪ dˌuːɪŋ ðə tʃˈælɪndʒ ɐɡˈɛn.
If any traceur in the group claimed that he had completed a difficult and dangerous challenge that should not be attempted unaided, he had to prove his claims by doing the challenge again.