This is very easy to include as long as you have a useful weapon upgrade to get. In aggression alone, you could search a Hand Cannon for a Follow Through deck or have this be like a second copy of Jarnbjorn in your deck. There are also many heroes with powerful hero-specific weapons like Gamora with her sword, any of Rocket's toys, or 2 of Black Panther's Wakanda Forever upgrades, so this is a nice tool for those decks. These player side schemes have done an awesome job of helping you make decks built around a few specific cards be much more consistent!

Also, the flavor text is a John Wick quote right?

This card's cost is 2 Per Player not 2. In a 3 player game for 6 it removes 9 which you can do for cheaper and more effectively with Spider-Man. Depending on the side scheme status, Even the Odds is likely a better play as well.

I get that Alliance means everyone can pitch in for the side scheme here but overall not a great include. Would depend on what you can cut for it. If you have less than 3 Overwatch and Psychic Manipulation in your deck then you don't have room for this.

I'd say you need 3 allies doing 2 THW or 2 ATK in play to feel good about playing this card from hand, but there is a lot higher upside if built around with readying effects like Command Team or Avengers Assemble!. I don't think you need to worry too much about getting a side scheme in the victory display since this isn't an early-game card anyways. There are probably better options if you're only looking to use this "fairly" as a bit of healing value, but for a deck built around it, it can enable some crazy combo turns.

This is an ally that needs a little more building around than the others in Cable's precon, but the upside is tremendous. Even without a minion in play, dealing 2 to the villain on entry makes up for only having 2 hp, putting this on-rate with other 3-cost allies, and when built around you should have no problem getting 3 damage. With one minion in play, Sunspot becomes a Valkyrie, and with two minions engaged with the same player, Sunspot can do 11 damage in one turn and be ready to block immediately in the villain phase...simply insane. If you want to play a -theme deck, be sure to include Captain Marvel as well. I look forward to playing an Iron Man deck with Sunspot, since his Repulsor Blast also encourages building with energy resources. Thor is another good choice, who makes lots of with God of Thunder and uses it to power Lightning Strike.

Do note that while you can always overpay for cards in Champions, you can't count them towards an ability like Sunspot's above the card's printed cost. See hallofheroeslcg.com for the relevant ruling on Moon Girl, which uses the same language as Sunspot.

Caliban is a solid ally with a Call for Aid-style response upon entry. This can be used in a few different ways - it can find a specific ally your deck is built around like Fantomex if that's the only target, it can load up your graveyard to increase the versatility of Make the Call, or it can activate Digging Deep/White Fox, which is a very strong use. Even without a combo, it's above rate for a 3-cost ally due to drawing a card when it comes in. The psionic trait also makes Caliban premium for psionic-theme decks. A very nice card!