GλOG: Item Templates

Lambda templates are associated with items rather than a character class. Gaining a λ template is simple: spend a downtime action training with the associated item. This may also require an XP investiture or be limited in other ways, such as once per level - ask your GM. You cannot gain the same λ template more than once unless otherwise specified.

A good λ template does not invalidate the need for the item, nor does it require the item to use. Rather, it complements the item and unlocks new applications for the associated item and the rest of the character's inventory. Not all items have λ templates. If a month training with an item wouldn't make you significantly better at using it in a mechanically interesting way, it doesn't need one.

Some of these items have Consumable rules. I've never found a satisfying solution to tracking inventory slots, so these are references to measure the scale of the item I'm writing about. Insert your own inventory tracking and encumbrance rules here - and let me know about ones that work best for you so I can crib them for my own games.

 Abbreviations: 1H = one handed, b = bludgeoning, p = piercing, s = slashing

Crowbar: 1H 1d6b, advantage on Strength tests to lift/pry/move objects
λ - Leverage: At a glance, you can see structural weaknesses in objects and constructs such as doors, walls, automatons, and siege engines, and you learn their current hit points. Once you know of a weakness in such a construct, you have advantage on melee attacks and damage rolls against it.
You can share the knowledge of a weakness with your allies so long as you have the time to accurately describe what you're talking about. Pitched battles don't count. 

Rope & pitons: Surfaces with a securely-anchored rope can be safely and slowly scaled without a test. Surfaces with a rope can be climbed at double speed. Consumable: Comes in 50' lengths of rope and packs of 2 pitons. Reusable.
λ - Second-Story Worker: Double your climbing speed. You can slowly and safely scale any non-sheer surface. Halve the difficulty of tests to climb surfaces quickly.
This ability is most obviously useful for a character to climb a surface, scout an area, then let down a rope for their allies to climb after them. 

Roll of bandages: During a rest, give an injured character temporary hit points up to the difference between their current total HP (including temporary HP) and their maximum HP. These hit points wear off at the next rest. Consumable: A single roll of bandages provides 12 temporary hit points before running out.
λ - Field Medic: You can apply bandages or other mundane medical treatments to an adjacent character with a single action, rather than a longer duration. Any temporary hit points granted this way expire at the end of combat or in 10 minutes, whichever comes first. You can't do this if you or the target character are engaged in melee combat.

Backpack: +2 inventory slots inside the backpack, +2 slots on the outside of the backpack. Items in the backpack are protected from mundane physical hazards like rain.
λ - Hoarding Impulse: Whenever you need a mundane piece of equipment that isn't listed in your inventory, you may make a Wisdom test. If you succeed, you have a ratty version in your bag that will work just this once and then break. Either way, write the item down next to this ability and cross it off; until you return to town for downtime, you can't get it from this ability again. 

Helmet: +1 AC. When you would suffer critical damage, you may splinter your helmet to reduce damage from that source to 1. Your helmet provides no further AC benefits and is disenchanted if magical.
λ - Warsight: You can see the HP, AC, Morale, and command hierarchy of enemy combatants. Roll initiative with advantage.
Warsight does not let you literally see numbers, but you gain that game-mechanical information. Much like riding a bike, you do not need a helmet to use Warsight, but you should wear a helmet anyway. 

Torch: 1H. Sheds light in a 30' radius. Covering a torch is a free action or reaction, but lighting a torch takes a full combat turn and 2 hands of fiddling with a flint and steel. Many things extinguish torches, including fighting, getting wet, and sprinting. Consumable: Every exploration turn, roll 1d6. On a 1, the torch is consumed and goes out. 3 torches take up 1 inventory slot.
λ - Torchbearer: You can wield a torch as an effective melee weapon without burning yourself or it going out. It deals 1d6 fire damage and the target must save vs. being set aflame for 1d2 damage a round. Burning ends when they take 2 damage from the roll, when they stop, drop, and roll, or when they are otherwise extinguished.
I chose the 30' range so you can see as far as you can move in one action. Look before you leap. 

Lantern: 1H. Sheds light in a 30' radius. Follows torch rules for lighting, but is more difficult to extinguish than a torch. Requires oil. Semi-Consumable: Every exploration turn requires 1 unit of oil or the lantern goes out.
λ - Lightbearer: While in a dark area, you and all allies within the radius of a light source you're holding (or casting if magic) have +1 to hit and +1 AC.
I want to incentivize players to engage with lighting mechanics. 

Healing herbs: When eaten, provides 1d6-2 temporary HP (negative temporary HP deals damage) and allows the character to save against up to one poison or disease effect. If saving against a poison or disease, causes nausea and induces vomiting. Any temporary HP granted at the beginning of the next rest. Consumable: One inventory slot of healing herbs is 10 doses.
λ - Nutritious Diet: Permanently increase your maximum HP by 3.

Tower shield: 1H. As an action on your turn, you may raise your tower shield. While the shield is raised, add your Strength bonus to your AC. To move, you must lower your tower shield (this is a free action).
λ - Shield Wall: Allies immediately behind you also gain the AC bonus from your tower shield while it's raised. 

Staff: 1H 1d6b, 2H 1d8b. 10' reach.
λ - Arcane Focus (Staff): While you wield a staff, you can use it to cast a spell as an action on your turn.
I'm playing around with the idea of more characters getting to cast spells outside of combat in rituals that take an exploration turn or longer. Dedicated casters take items and templates like this to cast complex spells to harm their enemies and protect their allies in dangerous situations.
This also counts as a 10' pole. Not all staves are 10' long, but if you want a 10' pole, get one of these. 

Dagger: 1H 1d6p/s. Throwable 30'.
λ - Sneak Attack: While you are behind, above, flanking, or concealed from an enemy, your attacks deal an extra 1d6 damage. If you fulfill more than one of these conditions, you also roll to hit with advantage.

Bottle of holy water: Deals 2d8 sacred damage to unclean, unholy, and undead creatures (halved on a successful Wisdom save). Throwable 30', consumed when thrown. Unclean, unholy, and undead creatures must make a Wisdom save to cross spilled holy water.
Spilled holy water evaporates over the course of an exploration turn.
λ - Sanctifex: During an exploration turn, you can bless a bottle of fresh water and turn it into 1 bottle of holy water. You can also perform a frantic blessing as an attack in combat, which forces an unclean, unholy, or undead enemy to make a Wisdom save or spend its next move action retreating from you.

Armor plate: +1 AC, -1 Initiative. Worn over one part of the body (arm, leg, or torso). You may wear up to 3 plates. If you are wearing more than one plate, you cannot move silently.
λ - Plate Carrier: You may wear up to 6 plates. 

Wizard hat: While you are wearing a wizard hat, you have +1 Magic Die.
λ - Magesight: You can see, smell, or taste magic beyond its material manifestations, making magical effects apparent to you. When making eye contact (or an equivalent mutual exchange of attention) with another spellcaster or magical creature, you immediately gain an instinctive understanding of its magical capabilities including total number of magic dice and number of magic dice remaining.
Wearing additional wizard hats or swapping wizard hats does not increase or replenish your magic dice. It is a funnel that draws power into the mind, not a sartorial affection - so sayeth the self-conscious mage.

Buckler: 1H, +1 AC.
λ - Parry-Riposte: Once per round, when an enemy hits you with a melee attack, you may make a Dexterity test. If you meet or beat their to-hit roll, you negate the hit and hit them instead.
The more armor you're wearing, the harder it is for you to parry, because attacks that hit you have higher to-hit rolls.

Vial of oil: Covers a 5' square in flammable (burns for 1 minute at 1d6 fire damage per round) and slippery (Dexterity save or fall prone in the space) grease, or powers a lantern for 1 exploration turn. A flask of oil contains 3 vials, a jug contains 6 flasks.
λ - Dungeon Chef: You can prepare Dungeon Meals from ingredients. To cook a Dungeon Meal, spend 1 exploration turn with a 1 vial of oil, a cooking pan or pot, and a blade. Make an Intelligence, Wisdom, or Dexterity test vs. 8 plus 1 for each ingredient you use. On a success, the meal is delicious and provides +1 temporary hit point per ingredient. On a failure, the meal is only edible as rations. On a critical failure, you waste the ingredients.
Dungeon meal benefits are in addition to the traditional GLOG benefits of taking a Lunch, which restores 1d6 HP. Cf. Skerples' Monster Menu-All for further information regarding dungeon ingredients.

Oversized weapon: 2H, 3d6-3 damage of a relevant type, 10' reach. Takes your entire turn to heft and attack. 4 inventory slots.
λ - Heavy Weapons Mastery: Add your Strength bonus to the damage of all your melee attacks.

Trenchcoat: +2 inventory slots. Caps your armor bonus to AC at +2.
λ - Deep Pockets: To solve an immediate problem, you may make a Wisdom test to pull a relevant mundane tool out of your bag that helps in this situation. The more obscure and valuable the item, the harder the test. If you succeed, it works once, then is consumed. Whether you succeed or fail, write the item down next to this one. You can't use this ability to gain that item again until you have downtime in town.

Lockpicks: Allows you to make Dexterity tests to open locks and disarm traps. Without lockpicks, you need a key, brute force, or a critical success.
λ - Tricky Fingers: Whenever you fail a Dexterity test to perform sleight of hand such as picking a lock, disarming a trap, or picking a pocket, your first failure doesn't alert the victim or trigger alarms.

Bow & arrows: 2H, 1d8p, 120' range, disadvantage on attacks within 30'. Quivers hold 30 arrows.
λ - Eagle-Eyed: You can always hit stationary targets within range with ranged attacks. This allows you to push buttons, break windows, and ambush guards with impunity.
If you don't make a roll to hit, you also cannot critically hit the target. This ability also works for thrown weapons, rocks, bows, guns, and even ballistae that you aim.