Soul wars is primarily played to gain zeal points in order to imbue items such as rings and slayer helmets. It also has some other unique rewards. There are no boosts or requirements for Soul wars.
To start a game of Soul wars, use:
/minigames soul_wars start
To check how many points you have, use:
/minigames soul_wars tokens
To buy the following items, use the command below. The pet is obtainable from Spoils of war.
/minigames soul_wars buy
Red soul cape
To imbue the following items, use the command below.
/minigames soul_wars imbue
Hydra slayer helmet
* - Currently unobtainable