Gameplay is pretty much identical to the Mega Drive version of Ristar, albeit scaled down to suit the Game Gear's specifications. Ristar can jump using the button, and can use his stretchy arms to grab on to enemies and headbutt them with the button. This is the only way to eliminate enemies as jumping on them will not work. Just like in the Mega Drive version, Ristar can also use his stretchy arms to climb walls, swing around poles and even swing on Star Handles to perform a Meteor Strike. Unlike the Mega Drive version, Ristar cannot swim and will instead sink to the bottom and act like he is on land, but he can still breathe.
The game uses the same health system: the player starts with 4 stars worth of health. Every time they're hit, they lose one star, but may replenish health by collecting items. Ristar also has a very basic life/continue system: once the player loses all of their lives, they'll be taken to a continue screen where they can choose to keep going with the game or give up. The password system, which was used in the Mega Drive version to enable cheats, is traditionally used to save the player's progress, and the player is given a password if they choose not to continue when they run out of lives.
Some of the items listed here are exclusive to this version of the game, such as the Big Stars and the Super Star:
Grants access to the Bonus Round after defeating the Round boss when collected.
Note: the level names were changed when brought to the West.
Round 1 - Planet Flora/Neer
Planet Flora is the first level of Ristar, and is set in a tropical island/jungle setting just like the Mega Drive version. Most of the Round is the same, except the mini-boss in the first area has been replaced with a wall of glass blocks to break through, and the second area will require Ristar to use spears to overcome trees. Riho remains in place as the boss of Flora, and is just as easy to defeat.
Round 2 - Planet Terra/Fanturn
The second Round replaces Planets Undertow and Scorch with a completely different planet that serves as a very large oddity. It is a dream-themed world that has the player go through a sky-themed area with fluffy clouds, rainbows and beanstalks to climb, and an area set on a pirate ship with masts to climb up and hooks to swing down on. For whatever reason, the first area of this Round has been dummied out in the Western releases, stripping the planet down to one area and the boss, but it can still be accessed by cheating.
The boss is a tapir-like creature who heals himself by sleeping and altering the world around him. The player has to first take out the bat that covers his lantern so he cannot sleep, then throw his pillows back at him. Defeating him causes the world to transform into a decrepit nightmare.
Round 3 - Planet Sonata/Neuos
With the absence of Planet Scorch in this version of the game, Planet Sonata is now the third Round. Like with Flora, Sonata is much like its 16-bit counterpart, complete with having to deliver metronomes to songbirds in order to proceed. Both of its bosses are intact, though the mini-boss has one less mechanical head to deal with due to the smaller screen.
Round 4 - Planet Freon/Timu
The second Game Gear-exclusive Round is also an oddity in that its first area is an ice level similar to the 16-bit game's Planet Freon, albeit with time-themed decorations, and even has the same name in the Western versions. The second area, however, is very different as the player will navigate a large clock tower.
The central gimmick of this Round is the presence of timed gates throughout both areas. When Ristar passes through one of them, a time bomb will be stuck to him, and the player must rush to a pool of water to get the bomb off Ristar before time runs out. The boss is a rabbit fought inside an hourglass, who will attack by either bouncing on Ristar or stopping time to shoot projectiles from his belly.
Round 5 - Planet Automaton/Rewope
Planet Automaton is the third planet to be ported from the Mega Drive version and is the fifth Round of this game. Most of it is the same as in the Mega Drive version, except the anti-gravity section in the first area has had its anti-gravity gimmick removed, and the mini-boss is replaced with a cluster of Big Stars for the player to grab. Uranim is fought in the same way as the Mega Drive version.
Round 6 - Planet Greedy
Castle Greedy holds the final fights against Inonis and Greedy just like in the 16-bit version, however the first section is different in that the player must ride an elevator and defeat a shower of enemies, with Adahan (the boss of the 16-bit version's Planet Scorch) making a surprise appearance as a mini-boss.
Bonus Stages are accessed in a different manner than the Mega Drive version in that the player must collect hidden Orbs within a Round and then defeat the boss at the end of the Round. If these conditions are met, they will be transported to a Bonus Stage.
Whereas the Mega Drive version would task the player with getting to treasure within the time limit, the Game Gear version instead has the player bounce about in a confined arena and collect as many Big Stars as possible without falling into a pit, and will be awarded 100 points for each star they get at the end. If the player manages to collect every Big Star, they will be awarded a Perfect bonus.