Collector's Monocle

Collector's Monocle Treasurer Gemsbok had this monocle custom made to enhance his perception in stealth strikes.

Tier UT
On Equip +140 HP, +8 ATT
Reactive Proc On Shoot: ATT↑ ATT boost (+12 ATT) on self for 4 seconds if the user is Invisible.
Cooldown: 1 second
XP Bonus 8%
Soulbound Soulbound
Feed Power 1,000
Forging Cost 60 Legendary Material / 160 Rare Material / 180 Common Material / 1560 Forgefire / 1 Oryx's Sanctuary UTs UT(s)
Dismantling Value 15 Legendary Material / 40 Rare Material / 45 Common Material

Loot Bag Assigned to White Bag
Drops From Treasurer Gemsbok

Blueprint Collector's Blueprint
Drops From Treasurer Gemsbok
Obtained Through The Tinkerer (50x Ancient Schematic)

Notes
The Monocle gives sublime HP and ATT boosts (equivalent to the T5 rings of each stat), but it’s main appeal is its massive +20 ATT total if you can go invisible. Assuming you can, the proc has an effective 100% uptime, with a long duration compared to its cooldown or the Cloak cooldown. A consistent Monocle far surpasses otherwise endgame rings like The Forgotten Crown.

Rogues are clearly an obvious choice due to their consistent invisibility, and can stack this item with the Cloak of Bloody Surprises for a total of +37 ATT (though the latter boost is not 100% uptime). Tricksters with the Prism of Shattered Light and Leather classes using the Turncoat Cape can also make use of it, and especially savvy players can use Ghost Pirate Rum for the same effect (this is usually used purely for speedruns).

History
When first released, the ATT boost originally had a cooldown of 1.4 seconds.

Untiered Rings
Collector's MonocleUT. Collector’s Monocle
Set Tiered Rings