A vivid and exaggerated picture emerges of a massive beast driven by an unquenchable thirst. Its terrifying strength is put on display through the sheer, unimaginable volume of water it consumes [תקות אנוש, מצודת דוד]. The focus rests heavily on the creature's interaction with the river and its surrounding environment as it quenches its thirst.
How the beast approaches this massive intake of water is understood in a few distinct ways. One perspective links the action to the creature's sight. Looking out at the rushing river, the beast believes it can drain the entire body of water [אבן עזרא, רלב״ג]. Alternatively, it takes in a single, massive gulp that covers the entire distance its eyes can see [אלשיך, תקות אנוש]. Another view suggests its thirst is so intense that it plunges its entire head into the river right up to its eyes [רמב״ן]. Taking a different path, the imagery may not refer to the eyes at all, but rather to the springs that feed the river. In this light, the beast draws up and swallows the waters of the river all the way down to their underground sources and wellsprings [מצודת דוד, מצודת ציון, מלבי״ם]. A completely unique approach shifts the focus away from the beast's drinking habits entirely. Instead, it is God who captures the creature simply by casting His gaze upon it, causing the mighty beast to tremble in terror before Him [רש״י].
The aftermath of this tremendous drinking effort brings further consequences, often involving obstacles or traps. The primary approach among commentators is that in its intense desire to drink the river dry, the beast lowers its mouth all the way to the riverbed. As the water is depleted, its nose crashes into the rocks and sharp obstacles on the bottom, leaving it pierced and battered [מצודת דוד, ביאור שטיינזלץ, רמב״ן, רלב״ג, אלשיך]. Other interpretations view the piercing not as an injury, but as an expression of the creature's raw power. The beast might flare its nostrils so wide to inhale air and water that they appear to be forced open by tools [אבן עזרא, רמב״ן]. Conversely, the beast's nose itself might act as the trap. When it flares its nostrils, it creates a powerful vacuum, sucking in and capturing all the other animals living in the river [מלבי״ם, תקות אנוש]. Finally, the entire scenario can be read as a rhetorical challenge directed at humanity. It asks whether it is even conceivable that a person could capture this colossal creature the way one catches ordinary fish, attempting to pierce its nose with hunting hooks [רלב״ג].