Troika*

In the near future, a stone has been discovered in a star that can be combined in specific ways to create a valuable jewel, or used alternatively to generate fuel. As an adventurer seeking fortune, you journey to this star with others, but your spaceship lacks fuel. Players collect heptagonal stones, aiming to gather three of the same number for fuel and three in numerical order to transform into a gem. Without fuel, victory is impossible; among those with fuel, the player with the most valuable jewel wins.