The Reinforced Echo Shard is a crafting material from the Deeper and Darker mod that upgrades Netherite gear into Warden gear at a 
Smithing Table. You’ll make it from an 
Echo Shard wrapped in 
Warden Carapace and 
Phantom Membranes, so it can only be made once you’ve killed a Warden.
Every piece of Warden Armor and every Warden Tool takes one, and it’s also what you’ll use to repair them at an Anvil. Crafting your first one earns the Sculk Engineer advancement, and it won’t burn up if you drop it in Lava.
Obtaining
Reinforced Echo Shards can’t be found in chests, so you’ll have to craft every one you need. The recipe takes 4 Warden Carapace, 4 Phantom Membranes and an Echo Shard, with the Echo Shard in the middle and the Carapace on each side of it.
The Warden drops 1 to 3 Warden Carapace each time, so a single shard can take more than one fight. Echo Shards come from Ancient City chests, and Phantom Membranes drop from Phantoms, which show up when you haven’t slept for a few nights.
Gathering the Materials
It’s worth collecting the Phantom Membranes before you head down, since you’ll need 4 for every shard, which is 36 for a full set of Warden gear. Staying awake for three nights or more will bring Phantoms to you, so you don’t have to go looking for them.
Ancient City chests are where most of your Echo Shards will come from, and they also hold the Warden Upgrade Smithing Template you’ll need alongside each shard. The Ancient Temples of the Otherside have Echo Shards in their chests too, often in bigger stacks.
Uses
Each Reinforced Echo Shard upgrades one piece of Netherite gear at a Smithing Table, along with a 
Warden Upgrade Smithing Template. The shard and the template are both used up, so you’ll need one of each for every piece you want to upgrade.
A full set of armor takes 4 shards and the five tools take another 5, so you’ll need 9 altogether, which is 36 Warden Carapace. It’s worth deciding which pieces you want first, as every one of them costs 4 Warden Carapace whether it’s a Chestplate or a Hoe.
Repairing Warden Gear
Warden Armor and Warden Tools are repaired with Reinforced Echo Shards at an 
Anvil, and each shard restores a quarter of the item’s durability. That’s a lot of Warden Carapace for a repair, so Mending is a far cheaper way to look after the gear.
If you’re short on shards, it’s better to save them for upgrades and let Mending handle the rest. The gear lasts a long time anyway, with 2,519 durability on the tools and up to 640 on the Warden Chestplate.
FAQ
Put an Echo Shard in the middle of a Crafting Table, 4 Warden Carapace on its sides and 4 Phantom Membranes in the corners. The Carapace drops from the Warden, the Echo Shard comes from Ancient City chests, and Phantoms drop the membranes when they show up at night.
It’s used with a Warden Upgrade Smithing Template to upgrade Netherite armor and tools into Warden gear at a Smithing Table. It’s also the repair material for all Warden gear, so you’re able to fix any piece with it at an Anvil.
One for every piece of Warden gear, which comes to 4 for the armor and 5 for the tools, or 9 for everything. That works out to 36 Warden Carapace, 36 Phantom Membranes and 9 Echo Shards for the full set.
Echo Shards are found in the chests of Ancient Cities in the Deep Dark, which is also where you’ll fight the Warden for its Carapace. The Ancient Temples in the Otherside have them too, usually in bigger stacks than the cities, so they’re worth looting once you’ve got a portal open.
