Another good DM mitigation could be that since the spikes expand and stab, they also partially stab the brawler’s hand. Lots of good tradeoffs for the players to consider here.
Is it worth the brawler taking damage to defeat this monster?
Does the monster have poison/cursed blood that will infect the brawler from shared stab wounds?
That’s pretty rad. Id probably have the ring break if the enemy is high tier, but at least fracture so you only have one more use after the first one.
Another good DM mitigation could be that since the spikes expand and stab, they also partially stab the brawler’s hand. Lots of good tradeoffs for the players to consider here.