- Joystick: Use the 4-way joystick to direct Rex (or Bloop, Spike or Gwen if you are player 2, 3 or 4) around the islands; try not to fall over their edges.
- Punch Button: Use this button to make Rex (or Bloop, Spike, or Gwen if you are player 2, 3 or 4) punch out at the Trogs; one punch shall stun them but several shall knock them off the island. If your triceratops has eaten a chilli pepper he (or she, in the case of Gwen) shall spit flames at the Trogs.
- 1, 2, 3 or 4 Player Buttons: Push these buttons to in order to start the game as Rex (player 1), Bloop (player 2), Spike (player 3) or Gwen (player 4).
These four dinosaurs are the protagonists of the game; Player 1 controls Rex (red), while Player 2 controls Bloop (blue), Player 3 controls Spike (yellow) and Player 4 controls Gwen (purple). They start each island in the top-left, top-right, bottom-left, and bottom-right corners respectively (like the four lords of Namco's Exvania would do two years later) - and they must collect all the eggs of their colour upon each island while avoiding the pursuing Trogs, but they can punch out at them to stun them, and knock them off the island if they do it enough times. They shall lose one life whenever they are caught and beaten to death by a Trog, fall off the edge of the island (or into a tar pit), get rolled over by a stone wheel or crushed by a green Trog's spring; however, they will receive an extra life every 500,000 points by default. Once a triceratops has collected all the eggs of his (or her, in the case of Gwen) colour, he (or she, in the case of Gwen) must go to the base marked "HOME" of their colour - and, once one of them does so, you shall all be treated to a cutscene featuring the triceratops who was the first to finish, dancing, with either "CONGRATULATIONS!", "NICE WORK!", "GOOD JOB!" or "DINO-MITE!" above him (or her, in the case of Gwen), and if there is more than one player, the text "75,000 POINTS FOR WINNING" will appear at the bottom of the screen.
These one-eyed cavemen are the antagonists of the game; the Brown ones shall only use their fists to beat the triceratopses to death if they catch them, while the Red ones use their clubs to generate holes in the ground and fires (as well as beat the triceratopses to death if they catch them), the Blue ones will emerge from the ground and roll stone wheels towards them, and the Green ones will bounce around trying to crush them with their springs. When a triceratops punches out at a Trog, he'll be momentarily stunned - and, if one is hit three times in succession, he will be sent flying off the island (however, another one will emerge from the ground to take his place). Also, if a Green Trog bounces onto a springboard, he'll fly towards and hit the camera before sliding down the screen; you shall also receive 1000 points if any Trog falls off the edge of the island, sinks into a tar pit, walks into a fire or gets crushed by a stone wheel. However, if you are playing the game alone and are knocked out by a Brown or Red Trog you have to wait an unnecessarily long time as the Trog eats your triceratops's flesh, burps, and burrows into the ground (but if you are not playing alone, the other players can punch the Trog three times to knock him off the island before he starts or while he is chowing down, and if they do it before he starts doing so, the knocked-out triceratops can recover) before the game continues - so it is more favourable to be killed by a Green one if playing alone, as they stamp your triceratops into the ground.
On the regular islands, there are five types of powerups, that will randomly appear in the cleared spaces (and can be collected to help the triceratopses):
- Roots increase your triceratops's speed; with each one collected, he (or she, in the case of Gwen) will become faster until the stage's end (or death).
- Horseshoes will generate a forcefield around your triceratops that makes him (or her, in the case of Gwen) invulnerable to the Trogs for a short time; they also cannot be forced over the islands' edges or into the enormous holes which are in the centre of some of them while the forcefield is in effect.
- Chilli Peppers will give your triceratops the power to spit fire at the Trogs and burn them, for a short period of time; they're worth 10000 points each.
- Ice Jewels will freeze all the Trogs that are on the current island, for a short time; they can also get knocked off the island with a single punch during this time, but when new ones emerge from the ground to take their place, you can still get killed by them (even though the others may still be frozen).
- Pineapples will transform your triceratops into a tyrannosaurus with the power to eat the Trogs (the first is 10000 points, the second 20000, the third 40000, and the fourth one and all subsequent ones 80000 but the point value is doubled for the Green ones); you will also receive 1000 points every time you crush one of your teammates, and kill them! However, you will eventually run out of tyranno-power and return to being a triceratops - which gives any triceratopses who now happen to have one less life after your rampage a chance to get their own back when a second pineapple appears. It is also worth noting that you should avoid the mushrooms that also occasionally appear on the islands as they will reduce your triceratops's speed.
On the fourteenth and fortieth islands, which are "Diamond Mine" bonus stages, as well as the forty-ninth one, which is "Trogs' Cave", after all the Trogs have been killed, there are three types of jewels (in the case of Islands 14 and 40, you have to try and collect them all between you, before a 15-second timer runs out, and in the case of Island 49, you have to collect them all between you, to finish the game); Rubies (500 points), Emeralds (1000 points), and Diamonds (2000 points). Powerups will also still appear on Island 49 after all the Trogs have been killed, so that you can collect the jewels quicker.