'What did he do?' Kurt thought to himself while taking a closer look at his wounds. A silver liquid penetrated them.
The only reason why Kurt was reckless enough to fight Grenald bare handed was because of his fast regeneration.
Now that Grenald had found a way to neutralize his regeneration, even if slightly, he needed to change his approach. And what do you know, he happened to pick up the visage of his spear embedded in the soil right at that very moment.
His next action was already set.
With a plan in mind, Kurt went on the offense by releasing a barrage of punches on Grenald, which had him pushed back.
The moment that happened, Kurt bolted for the spear. Fighting without a weapon, especially since it wasn't his style, wasn't a disadvantage Kurt wanted to suffer.
Grenald himself found some breathing room as, instead of trying to stop Kurt, he looked over to the ongoing battle between Ulrik and Cavarl.
Now was the best time, if there was any, to intervene.