BJP president Amit Shah on Friday took a dig at opposition parties by likening them to animals banding together for self-preservation against the 'Modi wave' in the country. "There is a campaign that all Opposition should unite. Whenever there is a massive flood, all snakes, mongooses, cats, dogs and even cheetahs and lions climb up a huge tree as they fear rising water levels," said Shah on the occasion of the BJP's 38th Foundation Day rally in Mumbai.