“ This is an idea for a basic weapon which I have adapted partially into a fighter subclass. Let me know what you think, because if it's any good, I may post the subclass.
Double Bulwark Shield
Melee weapon (martial, shield)
Category: Items
Damage: 1d6 per hand, 1d4 together
Damage Type: Bludgeoning
Item Rarity: Standard
Weight: 6
When wielding the Double Bulwark Shield in two separate parts, you gain +2 to your AC, +1 per hand.
When wielding two separate parts of the Double Bulwark Shield, you can take an action to bring the two halves of your shield together. Your movement is halved as long as the shield is brought together. If you move or attack after bringing your shield together this turn, you receive a +3 bonus to your AC. If you don’t move or attack after switching this turn, you and an ally directly behind you receive a +5 bonus to your AC. This action is known as Steadfast.
Once the shield is brought together, you may take a bonus action to become Steadfast even if you attack this turn. However, you may not move or attack after becoming Steadfast.
Taking apart your shield is considered a free action.”
“ The runoff from Mount 'Evil Volcano' has turned an area of small lakes below into a vision of hell. The mixture of acids in the lakes is of such strength that virtually any organic material touching is quickly dissolved. It is a melange of sulfuric, nitric and hydrochloric acids.
However, the place does harbor life, and its very strange, and very dangerous....”
“ The PCs are walking along the road, when suddenly a bunch of bandits attacks. The player's dismiss it has just a random encounter, when they find an ornate ring on the leader, obviously out of place with the seemingly poor bandits, who could only afford cheap leather and weapons. This ring has a symbol on it, which, if researched, sets the PCs on a quest. And from then on, the players don't look at random encounters the same way...”