蚍蜉撼树 (pí fú hàn shù): To overestimate one's own strength — Meaning & Stroke Order

With your current strength, challenging the champion is no different from an ant shaking a tree.

The critics' attacks on this master are nothing but an ant shaking a tree.

He wrote an article refuting that famous scholar, but everyone thought it was an ant shaking a tree.

A small company trying to acquire an industry giant is like an ant shaking a tree.