conditional N1 rare writtenliterary
〜であろうが / 〜であろうと — whether it be ~ (or not)
〜であろうが / 〜であろうと ・ であろうが
Builds on 意向形
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See 〜であろうが / 〜であろうと in real sentences
Jengo shows 〜であろうが / 〜であろうと the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.
Study it in JengoSources Compiled with reference to A Dictionary of Advanced Japanese Grammar. Editorial confidence: medium.