A Punch Dolphin is a drill-like fish that creates some of the holes in the TumbleSeed levels. The only thing it has in common with a dolphin is a unique diving behavior.
Location and Behavior
Punch Dolphins appear commonly throughout all the levels in the game. They remain underground until the player gets fairly close, then a hole begins forming and a dolphin punches outward and dives down.
Punch Dolphins will damage other enemies as they initially spawn from the ground, but will only damage TumbleSeed as they dive down the screen. Upon hitting TS, both the Punch Dolphin and TS will take one damage, causing the dolphin to instantly die and drop 1-2 crystals.
Dolphins do not pose much of a threat unless TS happens to be right on top of one when it spawns or underneath its downward path. Their hole-forming animation begins a few seconds in advance of when they start to dive, making them easy to see beforehand and avoid. Whenever you are moving up to a new height in the level, keep an eye on the area above you, and dodge horizontally for holes that may begin to form there.
With the right timing, it is possible to kill a Punch Dolphin with weapons like the ThornVine. However, usually it is not worth attempting this because the dolphins disappear when they reach the bottom of the screen and only drop two crystals at most. The weapon cost investment is only worth it if you are able to kill multiple enemies with that same weapon.
Punch Dolphins are advanced forms of Hole Makers that learned to use their upward-punching momentum to dive and become greater threats. After they punch their hole, they fly down to the base of the mountain where they join a massive pile of other Punch Dolphins who are stuck there since they don't have legs. Unfortunately as a result of this, no Punch Dolphin who has learned the diving technique has been able to warn the other Hole Makers that it's a bad idea, and thus the endless cycle of tragic diving continues.