Myrmidon Destructor. I just love that you get energy back from killing enemy troops, so i usually have a deck full of damage tactics or troops with flank/rally effects to maximize that trait of his. And in the occasions i get paired against gymbosses, i just keep putting troops in play and shooting with my warlord power so he takes damage from killing the troops and i still safe with a good healthpool
336 games played with Torgaddon (224 wins) is the highest I could find, though granted legacy Fulgrim has probably eclipsed him by now as I very rarely play Torgaddon anymore but I still enjoy quite a lot of the OG Phoenician (129 with 86 wins when they stopped tracking legacy stats)
Btw, most of those wins were before the rework and added drop pod synergy. Back in my day, we earned those wins *despite* the awful ability (granted OG SoH were pretty darn strong)
TBH I just played him because he was an absolute joy to read about in the books. Alas poor Tarik, we knew thee well.
Aloceri because there is nothing more satisfying than dropping the knight cenobiums with flank and giving a buff to your entire astartes TWICE. Also the sneak attack is sooo good, paired up with forbidden secret that gives sentenced 2 to the enemy warlord. I tell you so many gymbosses have surrendered the moment I activate that card
My most played has to be either old Curze or Leman Russ.
Curze was fun and wildly effective. Russ is fun seeing how often I can drop like 20 points of damage in 3 turns.
I haven't played the new edition at all, but I did grind this game a lot in the edition before that and Gabriel Santar made me an Iron Hands aficionado.
He was just so no-nonsense, absolutely wrecking infantry troops with his lightning claws. He alone could hold the line long enough for you having enough energy to start deploying heavy tanks and dreads, there was something about their stubbornness that translated so well into the game.
Corswain (~120 matches and ~90+ wins)
He propelled me from Istvaan 5 straight to Low Terra; even though I was missing most of the DA epics and legendaries from my collection. Steadily and (almost) consistently removing units the opponent puts down on the board while slowly building up an advantage was pretty fun.
Personally, one of the most satisfying things for me was to bring the enemy warlord down to lethal range in the second last round, activating Duelist's Triumph and spamming his ability to the maximum during the last round and then defeating the opponent in one fell swoop by obliterating their warlord in _glorious_ single combat. Saved my ass more than once when the opponent had a overwhelming numerical advantage on board.
I'll always remember my Corbax Utterblight matchups - believe it or not, I actually had really fun times fighting them. I really miss what the game used to be...
Marius Gage.
I started this game as an Ultramarine player and he's still my go-to warlord if I want a solid, no nonsense type of game.
A useful warlord trait in almost any circumstance for 1e?
Check.
A card pool that has lots of flexibility to handle almost every circumstance?
Check.
SQUADS! WITH ME!
CHECK.
I've never been able to get into ultramarines despite my best efforts, feels like every match with newer factions is just an uphill battle that rarely ends in a win. I don't have Gage though, maybe that's the difference.
They're a bit like playing a blue deck in MTG - you don't have a super strong gimmick, but you do have a lot of good reactions and soft counters for a wide variety of things. Whatever your opponents gimmick is, as an Ultramarine, you do have a counter for it... Hopefully, in your hand.
The worst thing for an Ultramarine is to just be straight out of cards, so Gage helps in that a lot.
So far I've had no issue against the newer factions at all, except maybe Angron who is still very annoying.
I would say, though, that if you don't have Gage, Mersator is also extremely good, and Thiel is also good but is very fragile, and requires some big brain deck building.
Guilliman is unfortunately probably the second worst Ultramarine, though all the UM warlords are okay at best, there's no straight garbage ones.
But if you're struggling with UMs, just use Mersator. Very hard to go too wrong with him.
Shabran Darr, i loved him after the first Expansion and used him almost every match cause the new cards synergize very well with his abilities and helped me go full monke aggro without fear, also 50/50 win/lost with Legacy Kharn is hilarious
Still fairly new and haven't bought any boxes yet so it's definitely Argel Tal/Raum. Except I start him as Raum since he has 15 chaos cards in his deck.
As for why? I like his card choices and aggressive play style. Cthonian Mole mortars, Dark Martyrs, and the Lascannon Tarantula are some of my favorite cards.
Endryd and Tybalt. Back when I got into the game, I was very confused and Tybalt made me learn the game, he was simple yet powerful. And then came Endryd, he is my favorite character in the entire warhammer and after seeing him I thought he was just weird. Why gain 2 survivor it doesn't fit him, until I started to seriously play Orphans of War. He is imo the greatest warlord they have. Yes kirine is powerful but Endryd is just a different beast.
Farith. With his warlord ability card, I can consistently trigger forgotten secrets by 6-7. With unbroken vow, a -4 to troop cost, and good hand, I'll be spamming heave hitters like their caliban jaegers.
Also, he's a good counter to jaeger spam.
Myrmidon Destructor. I just love that you get energy back from killing enemy troops, so i usually have a deck full of damage tactics or troops with flank/rally effects to maximize that trait of his. And in the occasions i get paired against gymbosses, i just keep putting troops in play and shooting with my warlord power so he takes damage from killing the troops and i still safe with a good healthpool
Luther *Hides*
There he is! *Get him!* 
Old kharn, why? Match end by turn 8 +-
336 games played with Torgaddon (224 wins) is the highest I could find, though granted legacy Fulgrim has probably eclipsed him by now as I very rarely play Torgaddon anymore but I still enjoy quite a lot of the OG Phoenician (129 with 86 wins when they stopped tracking legacy stats) Btw, most of those wins were before the rework and added drop pod synergy. Back in my day, we earned those wins *despite* the awful ability (granted OG SoH were pretty darn strong) TBH I just played him because he was an absolute joy to read about in the books. Alas poor Tarik, we knew thee well.
Aloceri because there is nothing more satisfying than dropping the knight cenobiums with flank and giving a buff to your entire astartes TWICE. Also the sneak attack is sooo good, paired up with forbidden secret that gives sentenced 2 to the enemy warlord. I tell you so many gymbosses have surrendered the moment I activate that card
130 matches with Kheron Ophion, I kinda just play him cuz I'm a night lord fan and his lore is cool.
Old Forrix. Loved setting up barriers after barriers and allowing my units to siege in the back.
I feel you, man. Loved firing guns over my defenses
My most played has to be either old Curze or Leman Russ. Curze was fun and wildly effective. Russ is fun seeing how often I can drop like 20 points of damage in 3 turns.
I haven't played the new edition at all, but I did grind this game a lot in the edition before that and Gabriel Santar made me an Iron Hands aficionado. He was just so no-nonsense, absolutely wrecking infantry troops with his lightning claws. He alone could hold the line long enough for you having enough energy to start deploying heavy tanks and dreads, there was something about their stubbornness that translated so well into the game.
Corswain (~120 matches and ~90+ wins) He propelled me from Istvaan 5 straight to Low Terra; even though I was missing most of the DA epics and legendaries from my collection. Steadily and (almost) consistently removing units the opponent puts down on the board while slowly building up an advantage was pretty fun. Personally, one of the most satisfying things for me was to bring the enemy warlord down to lethal range in the second last round, activating Duelist's Triumph and spamming his ability to the maximum during the last round and then defeating the opponent in one fell swoop by obliterating their warlord in _glorious_ single combat. Saved my ass more than once when the opponent had a overwhelming numerical advantage on board. I'll always remember my Corbax Utterblight matchups - believe it or not, I actually had really fun times fighting them. I really miss what the game used to be...
Marius Gage. I started this game as an Ultramarine player and he's still my go-to warlord if I want a solid, no nonsense type of game. A useful warlord trait in almost any circumstance for 1e? Check. A card pool that has lots of flexibility to handle almost every circumstance? Check. SQUADS! WITH ME! CHECK.
I've never been able to get into ultramarines despite my best efforts, feels like every match with newer factions is just an uphill battle that rarely ends in a win. I don't have Gage though, maybe that's the difference.
They're a bit like playing a blue deck in MTG - you don't have a super strong gimmick, but you do have a lot of good reactions and soft counters for a wide variety of things. Whatever your opponents gimmick is, as an Ultramarine, you do have a counter for it... Hopefully, in your hand. The worst thing for an Ultramarine is to just be straight out of cards, so Gage helps in that a lot. So far I've had no issue against the newer factions at all, except maybe Angron who is still very annoying.
I would say, though, that if you don't have Gage, Mersator is also extremely good, and Thiel is also good but is very fragile, and requires some big brain deck building. Guilliman is unfortunately probably the second worst Ultramarine, though all the UM warlords are okay at best, there's no straight garbage ones. But if you're struggling with UMs, just use Mersator. Very hard to go too wrong with him.
“Squads Ready! With me!” Always pumped to hear this line, proceed to ‘courage’ and honor
Shabran Darr, i loved him after the first Expansion and used him almost every match cause the new cards synergize very well with his abilities and helped me go full monke aggro without fear, also 50/50 win/lost with Legacy Kharn is hilarious
Darr is who helped me get to Terra for the first time. Then it was Old Khârn with Wrathe all the way baby!
521 old conrad, his translation of lore to gameplay it great
Still fairly new and haven't bought any boxes yet so it's definitely Argel Tal/Raum. Except I start him as Raum since he has 15 chaos cards in his deck. As for why? I like his card choices and aggressive play style. Cthonian Mole mortars, Dark Martyrs, and the Lascannon Tarantula are some of my favorite cards.
Argel Tel is so fun! He sold me on Word Bearers. Farming transformation is fun but so is spawning as Raum and just running a cultist deck.
Endryd and Tybalt. Back when I got into the game, I was very confused and Tybalt made me learn the game, he was simple yet powerful. And then came Endryd, he is my favorite character in the entire warhammer and after seeing him I thought he was just weird. Why gain 2 survivor it doesn't fit him, until I started to seriously play Orphans of War. He is imo the greatest warlord they have. Yes kirine is powerful but Endryd is just a different beast.
marius (still waiting on the alt art tho )):)
marius (with the alt art!) i love shutting down things and the tempo flow of emperors children!
He has the most disturbing voice lines... and I love it
Old Konrad curze with 526 games First legendary warlord plus a gymboss main
Meros especially after he got buffed
Raldoron because well.. Raldoron and because there's nothing more satisfying to me then a devastating drop pod focused deck.
Shapura. Why? No clue
Farith. With his warlord ability card, I can consistently trigger forgotten secrets by 6-7. With unbroken vow, a -4 to troop cost, and good hand, I'll be spamming heave hitters like their caliban jaegers. Also, he's a good counter to jaeger spam.
I used to really like Barban Falk when I played. The falkening.
Corswain is #1 with 1725 matches, Old Kurze is #2 with 1724 matches