You can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest. The die changes size at higher levels: d6 at 6th, d8 at 11th, and d12 at 17th.
When a creature you can see within 60 feet of you fails a saving throw, you can use your reaction to allow it to reroll the saving throw. The creature must use the new roll.
You can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
Your Heroic Surge die now replenish on a short and long rest.
You can use this feature a number of times equal to your Charisma modifier (minimum once), regaining all expended uses when you finish a long rest.
Once you use this feature, you can’t use it again until you finish a long rest.
Additionally, whenever you succeed on a saving throw, you take no damage from the effect if it normally deals half damage on a success.