Companion Locket

Overview
Companion Locket is a trinket found in Plains Cave chests. It is a summon-oriented accessory that trades a portion of your total summon count for a large damage boost to every unit you do summon. This makes it especially strong for builds that can field several minions but do not need to fill every available summon slot.
Its bonus is tied to how many summon slots remain unused. Each summon slot has its own bonus damage percentage, starting at +100% for the first slot and dropping by 10% for each later slot. When you summon a unit, you lose the bonus attached to that slot, and the remaining unused-slot bonuses are added together to form the total damage increase for all active summons. In practice, this means the fewer summons you field, the harder each one hits.
A simple rule of thumb is:
- For 3 to 8 maximum summons, summon about half of your maximum summons, rounded up.
- For 9 to 12 maximum summons, summon 5 units.
- For 1, 2, or 13+ maximum summons, the trinket is generally not worth using.
For example, with 5 maximum summons, the slots are worth 100%, 90%, 80%, 70%, and 60%. If you summon 3 units, you lose the first three bonuses and keep the last two, for a total of +130% damage to each active summon. That is strong enough to make three summons behave like far more than three in terms of total damage output. With 7 maximum summons, summoning 4 units is a particularly efficient breakpoint, and the result can feel close to having around 10 summons without the trinket.
- The trinket is most effective when your build has more maximum summon slots than you actually want to fill.
- It rewards limiting active summons instead of maximizing their number.
- It is strongest in the middle range of summon capacities, where leaving a few slots empty gives a large cumulative damage bonus.
- It loses value when your maximum summons are very low, because there are too few unused slots to create a meaningful bonus.
- It also loses value when your maximum summons are very high, because the recommended active amount becomes too low to justify the accessory.
Other entities of this type
- Abyssal Cloak
- Accuracy Potion
- Aged Champion Chestplate
- Aged Champion Greaves
- Aged Champion Helmet
- Aged Champion Scabbard
- Aged Champion Shield
- Aged Champion Sword
- Air Vessel
- Alchemist Glasses
- Alchemy Shard
- Alien Costume Boots
- Alien Costume Shirt
- Alien Mask
- Altar Dust
- Amber
- Amethyst
- Amethyst Helmet
- Amethyst Staff
- Amethyst Sword
- Ammo Bag
- Ammo Box
- Ammo Pouch
- Ancestors Boots
... +1091 (see sidebar for full list)