As per the question, I'm looking for a decklist that is 1) Pure Rohan, i.e. no Gondor or other culture heroes, 2) It's the most competitive for solo play, but multiplayer-friendly as well, if possible. I have all the packs and I want to build a deck that shows what Rohan is capable of.
Thanks a lot in advance! 
P. S.: I'd like to summon the deckbuilding powers of @Seastan @Gizlivadi and the all the other genius deckbuilders in this awesome community
I play a lot Rohan recently because I love the new version I made with Eomund and Guthwine. Here is my decklist: http://ringsdb.com/deck/view/56936
I also made a more thematic (even if this deck is already pretty thematic) list here: http://ringsdb.com/deck/view/87879
There is other way to build a Rohan, around attacking staging area (Fastred, Dunehre, Eomer) and/or mount (elfhelm) but I found them way less effective.
Here is one of those less effective decks that Rouxxor is talking about! http://www.ringsdb.com/deck/view/82813
That is an Elf-helm driven deck which puts a bunch of mounts on the table. It lets the heroes do the work, and at its peak it does something like questing Eowyn for 5 and Theoden for 4, maybe even Elfhelm for 2 or 3. Ready 2 or 3 of them, defend with Eowyn for at least 6 (Golden Shield), or put that shield of Elf-helm and he can defend of 4 or 5 on the first attack and 3 on a subsequent attack (with Armored Destier). Then Theoden gets to attack for 8 on his first attack and 4 on his second.
It only has a couple of off-theme cards, which you could sub out (Errand-rider, Steed of Imladris, Elven Light).
Thanks to both of you, @Rouxxor and @GrandSpleen
In fact I happen to have recently built an updated personal take on the Rohan solo deck! Haven't published it yet, but this it: http://ringsdb.com/deck/view/70448 It does contain Steward, but with Leadership Éomer it's too hard not to take advantage of it.
Strategy is classic Rohan discard archetype, with all the current tools at our disposal: recur H´áma (or Elfhelm) with Gamling, as well as Snowbourn Scout with Guthwine. If you have Steward on Theoden and Gamling, you can basically recycle Háma "for free" each round and still keep getting Spirit resources. Pair that with Guthwine recycling Scout, and you have 3 reliable defenses each round with just your allies, assuming you can kill stuff that round with Éomer (which shouldn't be hard to use). Not only that, but there's also the Snowmane/Golden Shield combo with Éowyn. If you have both on her (again, very easy to do with Horsebreder and Open the Armory), she can quest for 4 and if successful, defend for 5 each round. The rest is just making a Rohan ally swarm,quest for a lot and attack for a lot. This one has beaten so far a fair few of medium to hard quests in solo like Helm's Deep and Pelennor. I hope you like it!
Edited by Gizlivadi7 minutes ago, Gizlivadi said:In fact I happen to have recently built an updated personal take on the Rohan solo deck! Haven't published it yet, but this it: http://ringsdb.com/deck/view/70448 It does contain Steward, but with Leadership Éomer it's too hard not to take advantage of it.
Strategy is classic Rohan discard archetype, with all the current tools at our disposal: recur H´áma (or Elfhelm) with Gamling, as well as Snowbourn Scout with Guthwine. If you have Steward on Theoden and Gamling, you can basically recycle Háma "for free" each round and still keep getting Spirit resources. Pair that with Guthwine recycling Scout, and you have 3 reliable defenses each round with just your allies, assuming you can kill stuff that round with Éomer (which shouldn't be hard to use). Not only that, but there's also the Snowmane/Golden Shield combo with Éowyn. If you have both on her (again, very easy to do with Horsebreder and Open the Armory), she can quest for 2 and if successful, defend for 5 each round. The rest is just making a Rohan ally swarm,quest for a lot and attack for a lot. This one has beaten so far a fair few of medium to hard quests in solo like Helm's Deep and Pelennor. I hope you like it!
Sounds AWESOME! Thanks a lot for sharing
I have recently discovered just how great Tactics Eomer is once equipped with Firefoot and Guthwine. I think a deck with him, Spirit Eowyn, and Elfhelm would make a pretty great deck.
You could go full on jank with T Theoden by using Snowmane, Golden Shield, Heir of Mardil, Day's Rising, and Herugrim.
18 hours ago, Gizlivadi said:This one has beaten so far a fair few of medium to hard quests in solo like Helm's Deep and Pelennor.
I wouldn't call those quests medium to hard! 
I understand him :). With mine I challenge the same on nightmare, and recently beat pretty easily Attack on Dol Guldur.
Yeah, as I've said many times I'm not interested in playing Nightmare, but considering the amount of people that do, I am more conservative when rating quests in here. Note as well that I am mostly a solo player and all of my decks are originally supposed to be played in pure solo.
I have two pure Rohan decks, which can Trample most scenarios. But they need two-player style.
18 hours ago, Gizlivadi said:Yeah, as I've said many times I'm not interested in playing Nightmare, but considering the amount of people that do, I am more conservative when rating quests in here. Note as well that I am mostly a solo player and all of my decks are originally supposed to be played in pure solo.
Among non nightmare quest Helm deep and even more Pelenor fields are pretty difficult. The second one can challenge a lot of nightmare. So we can say it is a difficult one ^^.
I forgot that solo was demanded on this thread. The rohan deck I show is more the multiplayer version. I also build a solo version (http://ringsdb.com/deck/view/64934) but I only play it a few times so it may see some changes in the future to be optimized for this format.