quick_wit. By my standards, a whale is:

Confident enough in their own analysis + trading ability to hold $20K>$100K of a particular stock continuously.

Be skilfull enough to manage a large inventory of shares over multiple price points with a flexible and reactive ability to trade for profit without affecting the market.

Not be afraid to bid at levels that others don't in quantities that others don't (often with hidden AON orders to confuse competitors and so as not to get partial fill paint downs from shorters / bashers).

Not be afraid to hit and take out the entire ask at crucial times (like when first to spot an update or upwards move opportunity) even when others not bidding.

All the above works for me on a continuing basis on $DIGX and many other stocks I cover here on IH.