Undue influence: burden shifts to dominating party when a transaction appears unconscionable, excluding ordinary business dealings. Undue influence exists where one party can dominate the will of another and uses that position to gain unfair advantage; this includes real or apparent authority, fiduciary relations, and contracting with persons whose capacity is impaired. If a dominating party enters an unconscionable transaction, the burden of proving absence of undue influence lies on that party, with a specified statutory evidence provision remaining unaffected; ordinary course business transactions are excluded.