If you don't know the rules, here they are.
In the Red Corner: A large squad of 20 Kroot, accompanied by a pack of 10 Kroot Hounds, emitting quite a stench. They are hungry for victory.
In the Blue Corner: A large squad of 13 Sisters of Battle stand ready to battle anyone in the Emperor's name. A Sister Superior wields an Eviscerator and reads inspiring tracts from the "Book of St Lucius" to the other Sisters. 2 of the girls are wielding flamers instead of bolt guns.
Neither squad is particularly quick, so there is no advantage for the assault.
The gates open!
It is the Kroot who win the roll to assault, which is going to make things very difficult for the sisters. At least they are in cover - the Kroot have no grenades and thus will be forces to strike last in the first round.
Kroot guns are only rapid fire, so they can't shoot. Instead they jump into the assault. The Sisters pray to their protector for Divine Guidance, succeeding due to their large squad size. Now they get +2 S but strike simultaneously. It was a hard decision whether to or but I thought they had better go for it if they wanted any chance of winning.
So everyone hits simultaneously. The Sisters can only manage 5 hits and only convert that to 3 wounds. Lacking an armour save, 3 Kroot are killed. Hitting on 3s and wounding on 3s means that the 90 attacks from the Kroot and Hounds convert into 46 wounds. Everything dies - it's ugly.
Aftermath: Just as we have reached the end of the first round of the tournament, a squad finally manages the first turn kill. The poor Sisters were never built for assault. They never had a chance without getting first turn, and even then hopes would be slim. The Kroot have prooved today that they are one of the squads to beat.