That's really the only difference. That and the fact that Bold Fighter is limited to Armored Units, while the Follow-Up Ring is exclusive to Arden. All things considered, Bold Fighter is definitely the superior skill.
Follow up ring allows arden to be defensive or offensive, just give him brash assault 3 seal (unless enemy spd is 15 or lower) and he will quad in player phase with brave sword no matter his hp, but he does loss to bold with the proc charge eff.
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