A better use for this ring using the same "shrinking something beforehand and using the ring to remove the shrink would be to make a flechette bullet from hundreds of metal spikes pre-shrunk to pin size. Fire the pins into your target, getting under their skin, then send in your brawler with the ring on his punching hand. The blows he lands would remove the magic and the spikes would return to normal size inside the target.
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?
A better use for this ring using the same "shrinking something beforehand and using the ring to remove the shrink would be to make a flechette bullet from hundreds of metal spikes pre-shrunk to pin size. Fire the pins into your target, getting under their skin, then send in your brawler with the ring on his punching hand. The blows he lands would remove the magic and the spikes would return to normal size inside the target.
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.