From Fallen London Wiki

Moods are temporary equipment items that grant far greater stat bonuses than normal items.

The original four moods, namesakes for the category, are boons with a +22 bonus to one of the four primary stats. (Formerly, they were Hats that granted +30.) They disappear from your inventory one hour after obtained. Compare them to adrenaline kicks.

It is not possible to have multiple instances of the same mood. (E.g. if you already have Alight with Passion and try to get another, you will still have only one.) However, if you have two different Moods at the same time, both effects will apply due to the unique mechanics of the Boon slot.

Mood name Equip effect
Preternaturally Intent +22 Watchful
Cool as Ice +22 Shadowy
Fired with Ferocity +22 Dangerous
Alight with Passion +22 Persuasive

Click here for a list of challenges with a base difficulty of at least 250.

These moods can be gained from these two rare opportunity cards and are accessible to characters of all levels.

A dusty bookshop
A little omen

There are currently also five additional moods found elsewhere in the Neath. Unlike the highly-similar basic moods, these affect a wide variety of stats, and last different lengths of time. Only by their ephemerality are they connected to the original set.

Mood name Equip effect Source Length
The Walls are Right High Nightmares Until TtH
An Epistemologically Flexible
Approach to Historiography
+1 Mithridacy Moulin expeditions 1 week
Not to be Trifled With +1 Dreaded Hiring assassins/Worming Until TtH
Lingering Contentment Prelapsarian Exhibition 1 week
Lingering Excitation Prelapsarian Exhibition 1 week