I will second this - I have yet to see any text in the rulebook that says we can't take special characters as allies. If you have found some, please feel free to point it out (and provide the source - preferably a quote with a page number).

Sorry if this isn't the right place, but can Eldar Fast skimmers with Star Engines now move 30" in the shooting phase?

Thank you for understanding that... I've been bringing that up every time fluff is mentioned. There are fluffy games and non-fluffy games. If you are playing a fluffy game, you are not electing to use any of the weirder combinations without an actually decent reason (and reasons or precedent can be found for everything on the list, though some are easier than others). If you aren't playing a fluffy game, why the hell do you care? Either way, most of the concerns presented don't strike me as valid.

As for "a demon prince working with Calgar", first note that SM+chaos are in the "not before the apocalypse" category, and thus cannot ally. If they both showed up in the same force as allied contingents (of, say, Tau) I would expect the two would be maneuvering to deal with the numerically superior threat (the guys on the other side of the table), hoping to get the other guy killed in the process, and if not, whittling down the number of "other" units so that there would be less opposition when they attacked each other. Do not mistake two sides shooting the same enemy as "trust". Even an SM-Tau "battle brothers" alliance probably boils down to "you're honorable enough not to stab me in the back while the other guy breathes, so we'll work with you first" outside of exceptionally unusual circumstances.

I swear, people like to claim this rule has all sorts of corollary abuses that are simply ridiculous. It's like they aren't even bothering to think of alternative explanations. IG+Chaos alliance availability is the best one; we all know that doesn't imply the two factions are friends, but rather lets you play a Traitor Guard force. Why do I feel like I'm the only one who even considers applying that same logic to the others?

Oh sorry, i did know about the SM+CSM allies being not before the apoc, I was merely using it as an extreme example as there I have seen many kids at my local store using the CSM+SM as allies, I didn't mean they could do it normally so i apologize for the misunderstanding.

It's fine, rules are still new and all. I think a lot of the negativity will die down after people get a chance to play with it more, speaking from experience with Warhammer Fantasy here; I was pretty upset about the changes of 8th edition, especially the magic system, but that evaporated after I got my first game in. Sure, there were some logical oddities like the comparative power of one Slann and ten Slann, but I've never seen more than one Slann in someone's collection, let alone on the table, so who cares?

They need two psychic tests, and two failed Deny the Witch rolls, yes. They also need a librarian within 24" who doesn't have any more pressing use for his psychic powers, and a PBS with clear line of sight to their target, meaning all those squishy T3/5+ models are in serious danger of being pulse rifled into the waiting arms of their Emperor for standing around in the open. And it requires at least ninety points of PBS and a hundred points of Librarian, to boot.

It's not a bad trick, if you can pull it off. But like a lot of Allies shenanigans it mostly just seems like it would be easier to buy more guns and knives, rather than tricks.

For those looking to have a fast moving ally that is capable of taking down 3+ save threats in close combat, the Imperial Guard's Rough Riders are quite strong in this edition.

For 145 points, you get:

Mogul Kamir, the Rough Rider's upgrade character which grants the squad Furious Charge, Fearless, and Rage (the latter being the most important).
10 Models total which can use the Hunting Lance, a special close combat weapon that can be used once per game to allow the models to strike with the strength of a crisis suit and and an initiative one higher than a standard marine (including being AP3 for charging with a power lance). The Rage special rule means the entire unit is making 32 attacks on the charge, enough to wipe out a full tactical squad of marines or bring down a T6 W6 enemy (technically, it's an average of 5.333 wounds against a T6 model, but that's pretty dang close).

Oh, and they're cavalry so they're fast enough to be wherever you need them, when you need them.

So I was going through my Ork codex and noticed something. The Bomb Squigs simply run at, and automatically hit, an enemy vehicle on a roll of a 2+. I checked the FAQ/Errata and didn't notice anything which indicated these guys can't simply run at a flier and hit them (and since there are no to-hit rolls involved, we don't care about Snap Shots) 5/6 of the time.

I'll be taking some as allies in our next tournament as an effective way to deal with fliers.

So I was going through my Ork codex and noticed something. The Bomb Squigs simply run at, and automatically hit, an enemy vehicle on a roll of a 2+. I checked the FAQ/Errata and didn't notice anything which indicated these guys can't simply run at a flier and hit them (and since there are no to-hit rolls involved, we don't care about Snap Shots) 5/6 of the time.

I'll be taking some as allies in our next tournament as an effective way to deal with fliers.