"Cubis Gold 2" is the full version of the free online game "Cubis 2." The gold version features two additional game modes, but all modes have the same basic rules. When you start a new game, you're presented with a list of rules and cube descriptions. The game also offers an "Interactive Tutorial" mode, helping you learn the rules firsthand.
The game starts with a set number of Cubes already on the board and you're given the option to place a new one where you want. You can shoot your new Cube from either the front or right side of the board, shooting the Cube so it lands next to a similar-colored Cube. Placing three or more of the same-colored Cubes either next to each other or under a Cube of the same color makes those Cubes disappear, scoring you points.
When you start a new level, some of the Cubes are stacked on top of others. You can only hit one of the lower Cubes with a new Cube; get rid of the lower Cubes and the ones on top fall. Cubes may stack three high. The triangular Wedge Cubes let you slide a Cube of that color under another Cube unless three are already stacked. When Cubes below an upper-level Cube gets removed, the Cube cracks upon hitting the board. Cracked Cubes break when hit by normal Cubes.
Other than the standard, Wedged and Cracked Cubes, other specials react differently upon use. Bomb Cubes blow up the Cube they hit and push away close-by Cubes. Laser Cubes melt targeted Cubes with lasers. Osmosis Cubes change the Cube they hit to their color and stack the two Cubes. Stone Cubes block access to all other Cubes. Dual Cubes may be matched with either of their two colors. Ghost Cubes, exclusive to the Morph-Fun modes, move around during play, making them harder to get rid of.
Each mode has 50 levels. You lose when you can't destroy enough Cubes within the given time. You also lose if you have no more spaces to fire your next Cube from. If you beat all 50 levels of one mode without "Random Level" enabled, the mode resets and you have 15 percent less time the second time around. This pattern repeats until you lose.