In every market there are whales and their main purpose it's to generate pump, but also to ACCUMULATE PRECIOUS coins at a very cheap price
Buying them without make noise, or rumors..
In which projects do you think the Wahles are involved' the most?
Size of what you call whale depends on a project. For bitcoin you must have $100M+ of cash you can risk. For smaller projects $1000-worth could be a whale. I would think of a whale as of someone who has enough funds to keep buying (or selling) moving the price 20-30%. Look for daily trading volume on coinmarketcap to get an estimation of how much money you need.