This mod is part of a series of mods that complement each other but are independent and can be used individually:
[ Equipment and Crafting Overhaul (ECO) ] -|- [ Legendary Effect Overhaul (LEO) ] -|- [ New Equipment Overhaul (NEO) ]

Featured in the Dank Suite mod collection. Check it out if you're interested in using my other fully standalone and highly compatible mods.

Overhaul and expansion of the legendary system. Fully modular and customizable to your own needs. Every feature can be configured in the blink of an eye via holotape or optional MCM.

Legendary Crafting and Swapping

• Craft, disassemble and/or swap all the legendary mods the game has to offer, including DLC and a plethora of custom ones.
• Disable crafting recipes so that you can only swap (detach and reattach) effects that you found on enemies.
• Add an optional 2nd, 3rd, 4th and 5th legendary mod slot to armour and weapons.
• Fallout 76's legendary effects for armour and weapons.
• A list of all available effects can be found here.
  

Controllable Legendary Effect Drops

• Inject LEO's custom and Fallout 76 effects into the legendary loot pool.
• Toggle legendary effect drops that you don't want to see in your game. Make certain drops more or less likely that way.
• Synchronise rules when using multiple mods that modify vanilla legendary effect drop rules.
• Reset all drop rules to their vanilla state if you prefer it that way or want to start from scratch.
• Optionally remove obsolete Nuka World's dummy legendary effects (they carry only an effect description for grenades) from the legendary drop rules and free up space.
  

Legendary Patcher (optional)

• This is an optional part of the mod. The main download includes a patcher plugin and item sorting rules for M8r98a4f2's Complex Item Sorter.
• The patcher plugin enables you to automatically patch equipment that is missing the vanilla legendary attachment point and adds LEO's bonus slots to custom/mod-added legendary effects.
• This part renders patches for LEO pretty much redundant.
  

RobCo Patcher Support (optional)

• This is an optional part of the mod. The main download includes a file that enables additional functionality once you install RobCo Patcher.
• The patcher automatically applies the first/vanilla legendary attach point to all eligible equipment found in your load order that doesn't already come with that slot by default.
• Using the patcher won't make all those items drop with legendary effects. It only allows you to apply/craft a legendary effect on the items that haven't had a legendary slot before.
  

Miscellaneous (optional)

• If you want to apply legendary effects to your Automatron robots as well then you can do so now: Legendary AutoBot (LAB) - Craftable legendary effects for Automatron robots
• Canary Save File Monitor Support: This is optional, you don't have to use Canary but if you do you'll benefit from LEO supporting it. You'll get notified when you load a save file that suffers from data loss that would affect LEO's functionality. There's no downside in running it, just upsides. More on the mod's function can be found on its mod page: Canary Save File Monitor
  

If you want to craft, swap or just detach legendary effects and apply the extra slots to an item you can do so on any armour/weapons workbench.

• Go to a workbench of your choice and choose any kind of legendary mod option (even "No Legendary Effect" works here).
• This adds the slots "LS: Extra Legendary Slots" and "SO: Scrap Option".
  

In case you're applying a second legendary mod to an item be aware that those effects won't show a legendary mod description below the item name but the effects will still apply.

Dynamic Slot Menu Structure:
L1: Legendary Mod Slot
├─ LS: Extra Legendary Slots
│├─ L2: Legendary Mod Slot
│├─ L3: Legendary Mod Slot
│├─ L4: Legendary Mod Slot
│└─ L5: Legendary Mod Slot
└─ SO: Scrap Option

Different ways of crafting and swapping legendary effects

• The easiest and most natural way of utilising legendary effects is by acquiring legendary items from enemies or other sources. Go to the workbench with them and remove the legendary effect by selecting "No Legendary Effect" in the menu. This will add the effect as a loose mod to your inventory. And that loose mod with its effect can be applied to other items you have without any requirement. You can limit yourself to this option by disabling legendary recipes via holotape or MCM.
• The second and more advanced way is by scrapping legendary items (items which have a legendary mod applied). You'll receive "Legendary Microchips" for that process. They can be used to craft any legendary effect the mod has to offer, provided you meet the requirements (amount of Legendary Microchips and perks).
• The Legendary Specialist perks are learned from magazines distributed across the Commonwealth (hint: overseen by individuals that may or may not be dead). They can also be bought from vendors (hint: major social hubs). The exact locations are listed in the FAQ article. If that's too cumbersome you can cheat the perks in via holotape or MCM.
• Additionally, if you've invested into the Fortune Finder perk you'll have a small chance (depending on the perk's level) to find Microchips in some containers across the game world.
• Loose mods of legendary effects for the first legendary slot L1 can be converted to fit the other slots (L2, L3, etc.). Detach a legendary effect in L1 and a conversion recipe for the same effect will become available in the other slots.
  

You can configure and customize LEO to your liking. There are two ways to do that directly in-game.

Holotape
The holotape is injected into your inventory on game start, once you've left Vault 111. It can also be crafted from the Chemistry Station, found under the LEGENDARY EFFECT OVERHAUL section. All the available options have descriptions. Tweak available slots, recipes, inject the new legendary effects into the game's legendary loot pool, remove ones you don't want to see as drops, tweak microchip returns when scrapping legendaries, etc.

Mod Configuration Menu (optional)
This is optional. The MCM configuration becomes available as soon as you install Fallout 4 Script Extender (F4SE) and Mod Configuration Menu. This menu sports exactly the same options as those in the holotape but presented differently.

• FAQ - Frequently Asked Questions
• List of all LEO legendary effects and their description
• Tutorial - Adding LEO support to custom legendary effects
• Tutorial - Adding legendary attachment points to items
• Tutorial - Identifying duplicate recipes for legendary effects in other plugins
  

The plugin comes in form of an ESL-flagged ESP file. Due to the ESL flag it won't count towards your ESP/ESM plugin limit but can be sorted like any other ESP.

LEO is incompatible with mods that modify the vanilla legendary effects. They'd override each other and restrict/hinder their features. It would require a patch to make those mods work properly alongside LEO. Mods that severely alter the "LegendaryItemQuest" and its script properties might cause LEO's controllable legendary drop feature to break. Other than that there's nothing that could prevent LEO from working as intended.
If you want to quickly check for compatibility when it comes to potential form conflicts in the plugins I recommend you use FO4Edit's "Filter for Conflicts" feature.

When it comes to supporting mod-added items that don't have a legendary slot or in case of mod-added/custom legendary effects not supporting LEO's bonus slots you have three options:

• either use the "Legendary Patcher" plugin (part of this mod's main download) for Complex Sorter to automatically patch your entire load order
• or use the guides linked above to add LEO support manually via FO4Edit.
• Hope that somebody else has already created a patch. Those can usually be found above in the "Requirements" menu under "Mods requiring this file".
  

LEO also doesn't work properly in the VR version of the game due to LEO being created with a more recent engine version while the VR version's engine is quite old, outdated and doesn't support all features. However, the older iteration of ECO is fully functional within Fallout 4 VR and contains most of LEO's legendary features.