As legendary warlords meeting in the fabled arena of Ortus to decide who is superior, both players command a band of handpicked warriors, all schooled in one of the prime elements. The Ortus arena is believed to be the origin of all things, the place where the prime elements were fed with the raw energies to shape the world as we know it. How true this is can be debated, but this is the only place where energy still flows freely in its purest form. Players must harvest these energies and channel them to their warriors as fast and unpredictable Wind warriors, clever positioning of supporting Fire warriors, and devastating blows from lethal Water warriors will all be necessary to claim victory.

Ortus takes place on a hexagonal board, with each player starting with eight warriors (two of each element) on the back row (the "Haven") in an order of their choice. Ortus is played in rounds, which each consist of four stages:

- Collect energy: Each warrior on an energy well generates energy, which flows into the player’s general pool.
- Maneuver warriors: Players can spend 1 energy per hex to move warriors to better locations or attack opposing warriors.
- Return the fallen: When the active player returns his fallen warriors to his Haven, his turn ends.
- Defend: Energy remaining from the maneuver phase can be used to defend warriors against incoming attacks; more specifically, each attack has a certain power, and if the defender is unable or unwilling to pay energy equal to this power, the warrior falls.

When a player occupies five energy wells at the start of his turn or has removed all eight opposing warriors, he wins.

Ortus has a gentle learning curve, starting with the Basic game, which can be taught in around eight minutes. From there, players can introduce the special rules for each of the elemental warriors one at a time to learn the full Advanced game. Each warrior has two unique skills that differentiate it from the others. Being able to move all of your warriors on the board gives an enormous amount of tactical options. The excitement of the game lies in the careful planning of your attacks, knowing when to advance and when to withhold Energy as well as knowing whether to save or sacrifice your warriors.