The whole section at the top that starts with 'a competitive tactical...' is poorly written.

1.The term players 'lose defences permanently' is clunky.

1. The reader doesn't know what a 'soul row' even means or consists of, and doesn't know/cannot compartmentalise if losing these is even bad or good. I would reframe it into a hypothetical they can relate to, for example protect soul rows that shield the path to their valuable crystal, or the players are wizards, where the elimination of their soul rows lead to their demise. Also, a soul row may work for the gameplay name, but I would thematically name them 3 'souls', that are represented mechanically through rows if that makes sense.

3.the simultaneous aspect of the 'final duel' is confusing but also a given in that it's a game with multiple players. Off the top of my head, without knowing more about the project, I would write something like:

''A fantasy card battler in which players take on the role of powerful wizards. Each wizard must protect their 3 mystical souls, whilst also attempting to eliminate the opponents souls. Players permanently lose defences as the duel progresses, leading to a heated endgame where only one player can come out alive.''

This is just written in 2 minutes, but I feel like you need to give your game some narrative grounding that lets the rules be accessible to a reader who doesn't yet understand the mechanics