While I agree with others that 30% may not be sufficient, you can still take the chance by considering the following:
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You might get to learn something different in this new job
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Each city has its own culture regardless of it getting more cosmopolitan each day
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If you are not moving with family then you might be able to manage in 30%
If you are fine with the above perspective, you can resign and while you are on notice period you can keep looking for better offers in your current city or in Bangalore; you should do this only if you are ready for the case where you don't find a better offer and have to move to Bangalore with a 30% hike.
There's also a probability that your current company may try to retain you.
So think from these different perspectives and then decide.
Wishing you the best!