Really, it depends on what the skills are. Someone who has trained a moderately deadly skill 1000 times is probably more scary than someone who simply knows even 1000 really deadly skills, but isn't especially good at using them. On the other hand, those same 1000 skills are likely more scary than someone who has trained a mediocre skill 1000 times. In the context of this wiki, I would probably say 1000 skills, just because some of the abilities on this completely outclass others (even ignoring absolute/almighty, etc), and it would be more scary not actually knowing what your opponent is capable of, than knowing the fundamentals that they have and just trying to figure out what they might use them for.