Excess combat damage dealt by Hill Troll (damage that is dealt beyond the remaining hit points of the character damaged by its attack) must be assigned as an increase to your threat.

"Mutton yesterday, mutton today, and blimey, if it don't look like mutton again tomorrow."
–Troll, The Hobbit

Cannot have attachments.

For each point of excess combat damage dealt by Great Cave-troll (damage that is dealt beyond the remaining hit points of the character damaged by its attack) remove 1 progress from the current quest.

Excess combat damage dealt by Hill Troll (damage that is dealt beyond the remaining hit points of the character damaged by its attack) must be assigned as an increase to your threat.

"Mutton yesterday, mutton today, and blimey, if it don't look like mutton again tomorrow."
–Troll, The Hobbit

Cannot have attachments.

For each point of excess combat damage dealt by Great Cave-troll (damage that is dealt beyond the remaining hit points of the character damaged by its attack) remove 1 progress from the current quest.

While Louis is engaged with a player, all Troll enemies gain

"Forced: After this enemy attacks, the defending player must raise his threat by 3."

Response: After defeating Louis, you may choose and discard 1 “Sacked!” card from play.

While Morris is engaged with a player, all Troll enemies get +1

Response: After defeating Morris, you may choose and discard 1 “Sacked!” card from play.

While Stuart is engaged with a player, all Troll enemies get +1

Response: After defeating Stuart, you may choose and discard 1 “Sacked!” card from play.

Forced: After Rupert attacks, shuffle all copies of the “Sacked!” card from the discard pile back into the encounter deck.

Response: After defeating Rupert, you may choose and discard 1 “Sacked!” card from play.

If there is no Hill Troll in play, Anduin Troll Spawn gains surge.

Forced: At the beginning of the combat phase, Anduin Troll Spawn engages a player engaged with a Hill Troll.

While Savage Hill-troll is in the victory display, each Troll enemy gets +1 hit point.

Shadow: If attacking enemy is a Troll defending character does not ready during the refresh phase this round.

Forced: After Rob and Bob makes its first attack each round, if there are two or more players, it engages the next player and makes an additional attack (discard and deal a new shadow card for this attack).

Yes, I am afraid trolls do behave like that, even those with only one head each. –The Hobbit

Forced: After Louis attacks, the defending player must raise his threat by 3.

While Louis is in the victory display, each Troll enemy gains,"Forced: After this enemy attacks, the defending player must raise his threat by 1."

Immune to player events.

While Morris is in the victory display, each Troll enemy gets +1 and gains "Immune to player events.".

Rupert's cannot be reduced.

While Rupert is in the victory display, the of each Troll enemy cannot be reduced.

Cannot have player attachments.

While Stuart is in the victory display, each Troll enemy gets +1 and gains "Cannot have player attachments."