Reducing toughness is very different from dealing damage.
Toughness tells you how much damage can a monster withstand. From the Reference Guide, "Monster" (page 8)
When a Monster has lost Health equal to or greater than its
toughness, it is defeated.
Toughness almost never changes. Several monsters (mainly epic ones) have variable toughness. ...
Let's look at the exact wording on the cards:
Whenever you roll a 1 during a test, you may reroll that die.
When resolving a test, if you do not roll any 1's, you may reroll all of your dice.
You can trigger Skids' ability whenever you roll a 1 during a test, that is apparent.
Composed on the other hand is triggered ...
Voice of Azathoth
When an investigator would gain an Artifact, he may gain the Massa di Requiem per Shuggay Artifact instead.
At the end of the Mythos Phase, an investigator may spend Clues equal to [Number of Players] and discard the Massa di requiem per Shuggay Artifact to solve this Mystery.
The Green Flame
When this card ...
A response from Nikki from FFG that strongly implies the active mystery is all but pointless once the Ancient One card flips and the Final Mystery begins (meaning that if one were to solve it, it would not add an extra clue):
Syzygy is unique from other Ancient Ones in that it is designed to always flip. The cosmic alignment will occur whether the ...
All of the expansions for Eldritch Horror add content to the base game and require the base game to be played regardless of whether or not they include a new board.
Each expansion with the exception of the latest, Masks of Nyarlathotep, contain content that is usable with just the expansion and the base game and their content is independent of the other ...
From the rules reference, page 11:
An investigator can resolve a Spell card's effect as described on the
card. A Spell card’s effect may be triggered by a specific event or
require an action.
The rules don't explicitly define a "Spell Effect", so we use the above to determine that it means the effect of a Spell card, whether cast or activated ...