Sentinel.

Reduce the cost of the first Rohan ally you play from your hand each round by 1 (to a minimum of 0).

"Arise now, arise, Riders of Théoden!" –The Two Towers

Response: After a Rohan ally you control is discarded from play, exhaust Gamling to return that ally to your hand.

"...we have a thousand fit to fight on foot," said Gamling, an old man, the leader of those that watched the Dike. –The Two Towers

Combat Action: Ready Háma. He gets +3 until the end of the phase. At the end of the phase, discard Háma. (Limit once per round.)

"I am the Doorward of Théoden," he said. "Háma is my name." –The Two Towers

Attach to a Rohan hero. Restricted.

Reduce the cost to play Herugrim on Théoden by 1.

Response: After attached hero is declared as an attacker, exhaust Herugrim to add attached hero's to its for this attack.

"Here, lord, is Herugrim, your ancient blade." –Háma, The Two Towers

Attach to a Rohan hero. Restricted.

If attached hero is Théoden, Snowmane loses the restricted keyword.

Response: After attached hero quests successfully, ready attached hero.

Suddenly the king cried to Snowmane and the horse sprang away. –The Return of the King

Play only after the resolving enemy attacks step is complete.

Combat Action: Exhaust and discard a Rohan ally you control to choose and discard a non-unique enemy engaged with you.

"Helm is arisen and comes back to war. Helm for Théoden King!" –Riders of Rohan, The Two Towers

Action: Discard 1 card from your hand to give Éowyn +1 until the end of the phase. This effect may be triggered by each player once each round.

Slender and tall she was in her white robe girt with silver; but strong she seemed and stern as steel, a daughter of kings.
–The Two Towers

Response: Exhaust Eleanor to cancel the "when revealed" effects of a treachery card just revealed by the encounter deck. Then, discard that card, and replace it with the next card from the encounter deck.

"Gondor wanes, you say. But Gondor stands, and even the end of its strength is very strong."
–Boromir, The Fellowship of the Ring

Dúnhere can target enemies in the staging area when he attacks alone. When doing so, he gets +1 .

Captains rode to meet him at the ford, bearing messages from Gandalf. Dúnhere, chieftain of the folk of Harrowdale, was at their head.
–The Return of the King

Action: Reduce your threat by 3 to give control of Wandering Took to another player. Raise that player's threat by 3. (Limit once per round.)

...but certainly there was something not entirely hobbit-like about them, and once in a while members of the Took-clan would go and have adventures. –The Hobbit

Response: After Lórien Guide commits to a quest, place 1 progress token on the active location.

"Indeed deep in the wood they dwell..." –Aragorn, The Fellowship of the Ring

Response: After Northern Tracker commits to a quest, place 1 progress token on each location in the staging area.

"What roads would any dare to tread, what safety would there be in quiet lands, or in the homes of simple men at night, if the Dúnedain were asleep, or were all gone into the grave?"
–Aragorn, The Fellowship of the Ring

Action: Reduce one player's threat by 6, or reduce each player's threat by 2.

"Welcome to Caras Galadhan!" he said. "Here is the city of the Galadhrim where dwell the Lord Celeborn and Galadriel the Lady of Lórien."
–The Fellowship of the Ring

Response: After you travel to a location, exhaust a character to place 2 progress tokens on that location.

Then Aragorn lead the way, and such was the strength of his will in that hour that all the Dúnedain and their horses followed him.
–The Return of the King

Response: Cancel a shadow effect just triggered during combat.

'The hasty stroke goes oft astray,' said Aragorn. 'We must press our Enemy, and no longer wait on him for the next move.'
–The Return of the King

Action: Choose a player. Shuffle that player's discard pile back into his deck. Remove Will of the West from the game.

"If Gondor has such men still in these days of fading, great must have been its glory in the days of its rising."
–Legolas, The Return of the King

Response: Cancel the “when revealed” effects of a card that was just revealed from the encounter deck.

"There is naught that you can do, other than to resist, with hope or without it"
–Elrond, The Fellowship of the Ring

Action: Choose an ally with a printed cost of X in any player's discard pile. Put that ally into play under your control. (The chosen ally can belong to any sphere of influence.)

"...we will fight on." –Boromir, The Fellowship of the Ring

Action: Choose an enemy engaged with a player. Return that enemy to the staging area.

The light of the torches and the fire flickered about them...
–The Hobbit

Action: Return 1 card from your discard pile to your hand.

The dwarves no more shall suffer wrong,
The dwarves of yore made mighty spells,
While hammers fell like ringing bells
In places deep, where dark things sleep,
In hollow halls beneath the fells.
–The Hobbit

Action: Choose a hero in any player's discard pile. Put that card into play, under its owner's control.

'Yes, fortune or fate have helped you,' said Gandalf, 'not to mention courage.'
–The Fellowship of the Ring

Attach to a hero.

Attached hero gains +1 .

"You are indeed high in the favor of the Lady!"
–Unnamed Elf of Lórien,
The Fellowship of the Ring

Attach to a location.

Attached location gets -1 .

"Power to defy our Enemy is not in him, unless shuch power is in the earth itself."
–Gandalf, The Fellowship of the Ring

Attach to a hero.

Action: Exhaust Unexpected Courage to ready attached hero.

"Here am I, naughty little fly;
you are fat and lazy.
You cannot trap me, though you try,
in your cobwebs crazy."
–Bilbo Baggins, The Hobbit

Response: After you play a Dwarf character from your hand, reduce your threat by 1.

"Nori, at your service." –Nori, The Hobbit

Response: After Arwen Undómiel exhausts, choose a character. That character gains sentinel and gets +1 until the end of the round.

...in whom it was said that the likeness of Lúthien had come on earth again...for she was the Evenstar of her people.
–The Fellowship of the Ring

Quest Action: Spend 1 resource to put Bofur into play from your hand, exhausted and commited to a quest. If you quest successfully this phase and Bofur is still in play, return him to your hand.

"Get up lazy–bones..."
–The Hobbit

Response: After you play Kili from your hand during the planning phase, seach your deck for Fili and put him into play under your control. Then shuffle your deck.

"Let us join the throng!"
–The Hobbit

Response: After Woodland Courier enters play, place 1 progress on a location (2 progress instead if that location has the Forest trait.

Action: Choose another player. That player gains control of Blue Mountain Trader. Then, the player moves 1 resource from the resource pool of a hero he controls to the resource pool of a hero you control, or Blue Mountain Trader is discarded. (Limit once per round.)

Attach to a Nolder or Silvan hero.

Attached hero does not exhaust to commit to a quest.

"...those who have dwelt in the Blessed Ralm live at once in both worlds, and against both the Seen and Unseen they have great power."
–Gandalf, The Fellowship of the Ring

Attach to a hero.

Action: Exhaust Unexpected Courage to ready attached hero.

"You cannot trap me, though you try,
in your cobwebs crazy."
–Bilbo Baggins, The Hobbit

Attach to a location.

Response: After attached location is explored, the first player draws 3 cards.

...anything that Hobbits had no immediate use for, but were unwilling to throw away, they called mathom.
The Fellowship of the Ring

Response: Cancel the 'when revealed' effects of a card that was just revealed from the encounter deck.

"There is naught that you can do, other than resist, with hope or without it."
–Elrond, The Fellowship of the Ring

Response: Cancel a shadow effect just triggered during combat.

"The hasty stroke goes oft astray," said Aragorn. "We must press our Enemy, and no longer wait upon him for the move."
–The Return of the King

Response: After a sentinel character is declared as a defender, it gets +2 for this attack. If this attack deals no damage, ready the defending character.

...but along in the porch upon the topmost step stood Beregond...
–The Return of the King

Action: Return a card from your discard pile to your hand.

The dwarves of yore made might spells,
While hammers fell like rining bells
In places deep, where dark things sleep...
–The Hobbit

Action: Discard Westfold Horse-Breaker to choose and ready a hero.

"Your own valour has done more, and the stout legs of the Westfold–men marching through the night." –Gandalf, The Two Towers

Action: Search the top 10 cards of your deck for any 1 Rohan card and add it to your hand. Then, shuffle the other cards back into your deck.

"More speed we cannot make, if the strength of Rohan is to be gathered." –Éomer, The Return of the King

Response: After Frodo Baggins is damaged, cancel the damage and instead raise your threat by the amount of damage he would have been dealt. (Limit once per phase.)

Frodo began to feel restless, and the old paths seemed too well–trodden. he looked at maps and wondered what lay beyond their edges... –The Fellowship of the Ring

Response: After Éomund leaves play, ready all Rohan characters in play.

"You I have not seen before, for you are young, but I have spoken with Eomund your father..." –Aragorn, The Two Towers

Attach to a character.

Attached character gains the Rohan trait.

"Nor indeed am I a stranger: for I have been in this land before, more than once, and ridden with the host of the Rohirrim, though under other name and in other guise." –Aragorn, The Two Towers

While committed to a quest, Escort from Edoras gets +2

Forced: After resolving a quest to which Escort from Edoras was committed, discard Escort from Edoras from play.

Attach to a location.

Response: After attached location is explored, the first player draws 3 cards.

The Mathom-house it was called; for anything that Hobbits had no immediate use for, but were unwilling to throw away, they called a mathom. Their dwellings were apt to become rather crowded with mathoms... –The Fellowship of the Ring

Action: Exhaust and discard The Riddermark’s Finest to place 2 progress tokens on any location.

"And there are no horses like the ones that are bred in that great vale between the Misty Mountains and the White."
–Gandalf, The Fellowship of the Ring

Action: Discard a Rohan ally to choose a location. Place 3 progress tokens on that location.

"Death! Ride, ride to ruin and the world's ending!"
–Éomer, The Return of the King

While Elfhelm is ready, he gains:

Response: After your threat is raised as the result of questing unsuccessfully, or by an encounter or quest card effect, reduce your threat by 1.

"But my lord sends word that we must set ourselves in readiness: orders may come for a sudden move." –The Return of the King

Action: Until the end of the phase, Rohan characters do not exhaust to commit to quests.

"But we must ride more warily; for war is abroad, and the Rohirrim, the Horse–lords, do not sleep, even if it seems so from afar." –Gandalf, The Two Towers

Response: After you play West Road Traveller from your hand, switch the active location with any other location in the staging area.

The dark world was rushing by, and the wind sang loudly in his ears.
–The Return of the King

Action: Until the end of the phase, all Rohan characters get +2

With astonishing speed and skill they checked their steeds, wheeled, and came charging round. –The Two Towers