At the energetic age of 18 (1925), Caballero joined the Philippine Constabulary where he honed to the fullest the versatilities of his arnis system. He formally named his arnis system “De Campo Uno-Dos-Tres Orehenal”. “De Campo” to counter the strikes of his opponent (Also means from the fields), “Uno” to fake or feint, “Dos” to counter the counter strikes of the opponent, “Tres” to hit (finish) the opponent and “Orehenal” a reference to the technique as his own original style. In recapitulation it could be deduced that the name