Carbine Supremacy

You've specialized your combat training with carbine weapons. You gain the following benefits while wielding any of these weapons, if you are proficient with it:

• You gain a +1 bonus to the weapon's attack rolls.
• Whenever you have advantage on an attack roll and hit and the lower of the two d20 rolls would also hit (or a creature has disadvantage on a saving throw and the higher of the two d20s would also fail), and the target is no more than one size larger than you (your size or smaller if your weapon has the light property), it must succeed on a Dexterity saving throw (DC = 8 + your bonus to attacks with the weapon) or gain 1 slowed level until the start of your next turn.
• You can wield this weapon in one hand. When you do so, you treat the weapon as if it would have the strength 11 property. If the weapon already has the strength property, its strength number increases by one step (from 11 to 13, 13 to 15, 15 to 17, 17 to 19, or 19 to 21). While wielding the weapon in one hand, you can't attack a target beyond the weapon's normal range.
• When you take the Attack action, you can choose to forgo one or more attacks to startle. For each attack you forgo, you expend 1 ammunition and choose a creature that is no more than one size larger than you (your size or smaller if your weapon has the light property) and is within your weapon's normal range. The creature must succeed on a Dexterity saving throw (DC = 8 + your bonus to attacks with the weapon) or become shocked until the start of your next turn. If you could already startle, instead you can do so as your bonus action.