I feel like Northstar is an overlooked ally. For a single card slot he can negate 3 boosts. Or chump block and negate 2 boosts. That’s a lot of value for one card, essentially three copies of Target Acquired hiding in a trenchcoat.

The value goes up with healing cards like Med Team or X-Mansion, so he can be sustained for the duration of a scenario.

And being able to stop a big boost card often does more than just reduce how often you have to go recover. “Perfect defense” builds rely on cards like Unflappable, Desperate Defense, Never Back Down, Not Today!, and Hard to Ignore. An unlucky boost can really throw a wrench into the works, so this insurance policy is easily worth it!

White Queen is great ally. Why? This card can really remove two statues in one turn (confuse or stun from hero and tough from villain by the attack). Also 2 thwart for basic ally is excellent and give a flexibility. What's more? Very good trait X-Men, and also not bad Psionic. Three points of life is a nothing crazy, but enough.

Rate (A-C) B+ Works well in solo/multiplayer, only downside is trait locked

This card has been such a boon for protection. You can leave it on big minions and just chip away at their health casually while you block their damage. I found it synergized as well with Jump Flip and Side Step, so you can avoid using a basic defense to trigger the card. Also amazing for Change of Fortune. If you're finding you're having trouble dealing with minions and protection, I highly recommend this card.

This is the card that convinced me that I needed to build Magik in Pool. When you can see and change the top card of your deck, this is practically just an Avengers Mansion for 1. Domino is obviously another good choice for this.

If you aren't playing a character who can see or fix the top card of their deck, it's not quite as valuable but will still be more likely to pay for itself than not. You can look at your deck in advance to see what it has the most resources of and guess that. You should win a bit more than a third of the time just by being aware of the resource costs in your deck. Without having to memorize your entire deck's resources to make the most of this, it might be smart to consider two general states of your deck. One at the beginning with no setup, and one with maximum setup. Ask yourself, "what resource will my deck have the most of with nothing on the board?" and "what resource will my deck have the most of once all my upgrades are out." Answering these questions will help you figure out what to try to go for to get the most likely draw at different stages of the game.

Or if you need a specific card for a combo, you can just guess the resource that beats that card and hope you get lucky.

Even this metagaming isn't necessary to get value out of this. Since wild beats everything and it's more likely that one of the 5-6 cards in your hand is a wild than the top card, a wild in hand is usually a guaranteed free draw.

One thing I dislike about this is that it's a hero action, which means you can't go alter-ego as Star Lord, swap a card in your hand with the top card of your deck, and use this to draw whatever you put on top. But you can at least do the swap the next turn before going hero.

This feels like a very underrated card with some decent non-pool allies. It costs 0 to get out and then can be used to heal up to 7 at your leisure.

At its cheapest, this is 4 ER to heal 3 and deal 3 damage. That alone would be a great value. At its most expensive, it's 8 ER to heal 7 and deal 7 damage. And this can be split up across several turns, used to make a basic ally effectively immune to consequential damage for up to 7 turns and then slap an enemy in the face with all of that damage.

So what are some good allies to use with Tic-Tac-Toe? What basic allies get the most out of being healed by Tic-Tac-Toe?

Snowguard can either have 3 thwart or 3 attack. Either of which dramatically increases the value of Tic-Tac-Toe.

Gambit is a bit more conditional, but can potentially end up with 3 attack and thwart. If he does, he's worth keeping around with this.

Storm is considered to have 4 effective thwart, letting you shuffle threat from one bad scheme to a less bad one.

Gamora in a Guardians of the Galaxy deck might be the best use of this, letting you put an event in your hand and making the cost effectively free.

Rocket Raccoon can just straight up massacre minions with 4 attack and overkill. And his 2 thwart wouldn't be a terrible use for this on turns with no minions out.

You can also get more value out of any of the attackers by equipping a Sidearm

Also consider heroes that allow you to mix aspects. Spider-Woman and Adam Warlock can make great use of this with non-basic allies. And it's great in multiplayer where you can heal the allies of teammates.

The weirdest thing about this card is just that the thing it's best at is negating consequential damage in an aspect that doesn't have consequential damage. It's a Pool card that's ideal for non-pool allies.