Flail of Force

Weapon (flail), legendary (requires attunement) This flail has a clear glassteel head with a large sapphire in the center. When touched the flail can be felt subtly vibrating, as if it can barely contain its power. You gain a +2 bonus to attack and damage rolls with the flail. Each time you deal damage to a Large or smaller creature it must succeed on a DC 15 Strength check or be pushed 5 feet back. While holding the flail of force you can use your action to spin the flail very quickly creating a small wall of force per the spell adjacent to you. This wall is only 5 feet tall, 5 feet wide, and lasts 1 minute. You can only create one wall this way at a time.