There are many, in a flash I can think for example: just don't say the reason (let the other party assume on his own), don't show too much power in the first place (gradually show his power), there is a novel that the MC get back up from an organization first then show his talent (so people think the power is from the organization), create second identity to show his power. Actually I have forgotten the story right now, but if it is really in one night become strong and then he show his strength but don't know the consequences and cannot have the solution.... then I personally think the plot need to be improved. I think it is enjoyable to read a novel with smart MC, that is my opinion.