If you use ICICI bank card for booking at goindigo.in , use promocode "FLYICI" to get 10% off on base fare, may not be much of a saving but worth a try if you don't have any other offer.
^ It says only two usages during the discount period per card. It would work great for you if you have 4 different master cards as you would then get 2000 off effectively.
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ezeego1 has a 350 off per ticket per passenger. So effectively you would save 350 * 4 * 2. Good deal IMO
Cleartrip: 25% instant Cash Back for ICICI Bank Netbanking, Credit or Debit Card holders on base fair of domestic filght upto a maximum of Rs.1000 per booking >>