In ordinary case- the burden of proof lies on the aggrieved party.

In case of unconscionable transaction- The burden of proof again lies on the aggrieved party but the other party can (in order to save himself) counter prove:

(i) That there is no strong relationship between parties

(ii) That he had disclosed all material facts

(iii) That he had given enough time and opportunity to the other party to receive competent and independent advice.