Hydrogen life beings felt threatened by O2 life forms because O2 life forms have a much faster rhythm. Hydrogen can only travel at near space light speeds. They cannot go beyond that. O2’s can go as fast as 4 times the speed of light. H2’s are much smaller and slower and more numerous because of a higher frequency of suitable bio-spheres. There is trade between oxygen and hydrogen breathers but very disastrous wars have been fought between these two civilizations in the past.