Collocations for indignant - adj.

be, feel, look, seem, sound | become, grow, wax
She waxes righteously indignant if anyone tries to contradict her.

make sb

extremely, fiercely, highly, very
‘He deserves to be thrashed,’ she protested, fiercely indignant.

almost, mildly, quite, rather | justly, righteously

about/over
She became rather indignant over suggestions that she had lied.

at
They were quite indignant at his remarks.