Sonic the Hedgehog 2 (8-bit)
Pick up speed and skim the surface of the lake, picking up Rings as you go. When you go under, don't go for too long without air, or you'll lose a Chance. Take a deep breath from bubbles that float up from some of the blocks. Or when a big bubble comes your way, use it to float toward the top of the screen.
— Description from the Instruction manual.
Aqua Lake Zone is the third Zone in the Master System and Game Gear game Sonic the Hedgehog 2. It follows Sky High Zone and precedes the Green Hills Zone. As with all other stages in this game, Aqua Lake Zone consists of two standard Acts followed by a shorter, third Act which contains the Zone's boss.
The surface areas sport an abundance of operational fountains and water features. While beneath the lake's surface, crumbling ruins provide Sonic with a dangerous obstacle course. Bubbles in Aqua Lake Zone are much larger (and more resilient) than you might be used to, in Mega Drive games. With these bubbles, Sonic can actually jump in and ride all the way up to the surface.
This mechanical sea lion attacks Sonic by means of an inflatable, explosive ball. Sonic must hit the ball as the Mecha Sea Lion is still in the process of blowing it up, in order to do any damage. Other attacks will be repulsed, as the machine simply bounces Sonic atop its robotic nose, before tossing him to the side of the screen.