Alrighty.
Judgment for Contest 147
I tried to consider multiple liaison parameters for each card - how's it play in an underling game? sycophant? importer? the rest?. I also made judgment based on how a new player would react to it, given that "teaching people dominion" seems to be my main way of interacting with the game lately.
Company of Paladins - Ally
When another player plays an Attack, you may spend a Favor to be unaffected by it.
I like this a lot more than the reserve-driven "call this to ignore an attack" that we used to see a lot of during the early days of the WDC. You are right with your concerns - the no attack games, the discouraging getting attacks - although the concept of building up and wearing down defenses sounds interesting to me.
Enlist Committee Ally
At the start of your turn, you may spend a Favor to move your cube to a set-aside Ally for it applies for you. Setup: Set aside three random Allies and give each player a cube.
I think this smooths out a lot of the issues you were having with first player moving, cards too good, etc. This is, however, going to feel real bad in four-player where one person just doesn't get an ally, and also maybe in 3p with Plateau Shepherds, League of Bankers, or Gang of Pickpockets. A more reasonable version might be "At the start of your turn, you may spend a Favor to remove one of the set aside Allies. If only one remains, swap this with it." which sort of brings in an election process but doesn't 100% hose player four.
At the start of your turn, you may spend 2 Favors to discard a Victory card for +2 Cards. Repeat as desired.
I really like this one. Kudos for including a 'repeat as desired'. Two favors might be kind of steep, but that's probably fine, it keeps it out of the non-Importer openings and is a strong effect.
Ally: Circle of Mages
When you gain a card, you may spend 2 Favors to exchange it for a non-Victory card costing up to $4.
This is pretty neat. I don't know if it needs the non-Victory clarification - given that you're using a different resource, i think it's fine for it to compare overly favorably to Alms.
Boat Dwellers - Ally
At Clean-up, spend any number of Favors, to set aside a Copper you would discard from play per 2 Favors spent. At the start of your next turn, put them into your hand.
I wonder if an Underling deck could generate Enough Favors to pseudotrash-juggle all your copper. Probably with a Throne or something. This seems like the sort of fun side-game I'd get distracted by and completely miss that someone was greening.
Horde of Barbarians
Ally
When you gain a Liaison, gain a Curse.
If it is the first Curse you gained this turn,
+1VP per 2 Favors you have (round down).
I'm not going to lie, i'd be frustrated at having to do math to figure out when to buy liaisons in games. Also if it's going to have compulsory curses, including at least one that will fire before you can get more favors into play, you should at least round up. This just feels like I'd dig a hole for myself and lose hard.
Order of Cryptkeepers
Ally
At the start of your Buy phase, you may set aside a card from your hand, putting one or more of your Favors on it. After you shuffle, retrieve a Favor from each card you set aside this way, and then discard it if it has no Favors on it.
FAQ: The Favors remain yours after retrieving them, so you can then use them on another card.
This is really clever. In the same way that Peaceful Cult secretly made Worshippers, you've secretly implemented Freeze tokens. I really like this, especially with reclaiming the Favors as they return. The entry you nixed for this was great too.
You can spend 4 Favors for your buy token, 5 favors for your $1 or action token...
This looks like a blast. I don't know if starting everyone with a non-card vanilla token of choice is the best idea in Importer games, but maybe that's fine. I suspect games with this Ally will be fairly quick.
Worker's Union
Ally
At the start of your turn you may spend at least 1 favor to trash a card from your hand. If you did, gain a card, costing up to the cost of the trashed card plus $1 per Favor spent.
Ah, the Transmogrified Butcher ally. This looks fun. It starts everyone in an Importer game with a $7, though, which is an absolutely brutal leadoff. That's probably fine, although I suspect the player who leverages three or four $3- and $4-cost gains out of that is probably going to come out ahead of the one who trashes their estate for a not-yet-functional KC.
I suppose the strength of this is really dependent on what the $4 is - Priest? awesome. Nomad Village? maybe less so (although the buy might matter). Conspirator? I'm assuming it's intentionally worded so that it's not shapeshifting the card you played, but instead providing a sort of tag-along effect on top of it, yeah? Might be a very large conspirator enabler, in that sense. It should probably exist.
Band of Adventurers
Ally
After playing a Liaison, you may spend any number of Favors to gain a card to your hand or onto your deck costing $1 per Favor spent.
I think this, more than other Allies, encourages you to amass favors; Is stockpiling favors fun? I know I was kind of "eh" on it when I tried to make an autoprovincing deck with League of Bankers during previews, but also, yknow, I had to get to 32 of those, so maybe that ordeal poisoned it for me. I think there might be a Haggler-enabled Guildmaster engine that'd let you empty them with... idk, seven haggler plays and a Guildmaster? Three and two guildmasters? It's not going to be common but it's something that should probably be addressed, but it's on the level of a Hermit-Market square combo in terms of obscurity so maybe that's fine.
Band of Rebels
Ally
At the end of another player's Buy phase, you may spend 2 Favors to play a card with exactly one type that they have in play, leaving it there.
I feel your pain on trying to get this to play nice with Durations and Commands; I don't think 'exactly one type' is the way to do it, especially considering we're fan card world and we do weird stuff like monotype Reserves and Reactions; even purely with canon cards, you've got a 12 of 31 "playable" pile rate in Allies, and of those, two (merchant camp, galleria) don't do anything for you during not-your-turn (and barring something like Wot Mouse), bringing the hit rate down below 1/3rd for the set. Worse, this may push play towards avoiding those "plain" cards, simply so your opponent can't get a bonus card on their next turn. I think this is conceptually doable, but don't think this is quite it.
Maybe this is just me, but allowing a played card to turtle seems Real Cheap for 2 favors. "1 Favor per $2 or @2 it costs (round up)" might be ok here? So a Sycophant plays on for 1 favor, a Wandering Minstrel 2, the Band of Misfits does an encore for 3 favors, etc.
Veteran Trainers Ally
When you play an Action card, you may spend 1 Favor per $1 or 1D it costs. If that's its entire cost, replay it and gain a copy of it.
FAQ: You can't spend 0 Favors, so if a card is discounted to being free Veteran Trainers can't be used on it.
This seems really strong; I think it makes things like Sycophants games incredibly split-sensitive, which might not be super fun for newer players that could overlook the combo or misjudge how strong it is. However, they're also not the end-all be-all of dominion, so they'll learn and learn fast, i guess.
Maison of Hoarders
Ally
When shuffling, you may spend a Favor. Otherwise, add a Copper from the supply to the shuffle.
This has an interesting effect of pushing the game towards a slog, but in a slog, Copper is not the worst junk to have. I think this would be one of the ones that makes Regular Liaison Play more important, as opposed to something like Coastal Haven where it's fairly ignorable. I'd hate to play a game with this, Importer for a Liaison, and Wall (although Keep and Fountain both love it). It's cool to see a card penalize overdraw in the way this does.
League of Freebooters
Ally
When you play a card from your hand, you may pay 2 Favors to play a cheaper card sharing a type with it from the supply, leaving it there.
The other Command-like in this contest. This is good. It'll be weird when people do fun stuff like chain cards on pile types like "Odyssey" after they've rotated away from the finale card in the pile (although tracking-annoying on things like Elder). I like it.
Caterer
Ally
At the start of your turn, you may spend 1, 2, or 3 Favors to gain a non-Victory card costing up to and a number of Coppers equal to 3 minus the number of Favors spent.
The banquet mimicry here is cute. I'd see if you could cut out the middle case so you don't scare the new players away with math and contingent phrasing - something like, "At the start of your turn, you may spend 1 Favor to gain a non-Victory card costing up to $5, then you may spend an additional 2 Favors or gain 2 Coppers." I know some of the people I've introduced the game to bounced off Border Guard hard because of the contingent phrasing on it.
Winner: Commodore Chuckles's Order of Cryptkeepers
Runners up: emtzalex's Veteran Trainers, Timinou's Shepherd Clan
Really I had a hard time cutting it off at two runners up (a new rule for myself, lest i end up listing everyone under the runners up/hon. mentions [again]), and many of these will probably fall on a spectrum of "Really Fun" to "Perfectly Workable", so everyone take a bow, great work.
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incidentally, had someone else won the liaison design contest, my ally entry would've been the League of Lurkers:
Sewer Dwellers Ally
When you trash one of your own cards, you may spend 1 Favor to either trash an Action from the Supply, or gain an Action from the trash.
(i'm sure there's refinements needed on it, but i still wanted to show it off)