Without having played with it (hopefully soon!), this will make Rhino so much easier to deal with in solo. Besides that, I think having more time to build up (Iron Man for instance) without losing to threat is always good.
Attach to the main scheme. Max 1 per scheme.
Increase the target threat value of attached scheme by 4.
This card is pretty good and has some awesome value depending on the player count. The highest value comes from playing Solo (partially because it can't be stacked, so having more players doesn't scale well with the effect).
I'll break down the more obvious values this card brings.
- The resource spent-to-threat removed ratio that FFG wants to go with is a little weird, but looking at cards like For Justice! and even Sneak By, it seems that 1 resource equates to 1 threat removed. Allies like Maria Hill or Thor's Defender of the Nine Realms are more-so outliers rather than good indicators of value here.
- Therefore this card, in essence, is a 3 cost for 4 threat mitigated. Notably, it's not removed. But still, a pretty good ratio.
- Removing threat versus increasing the amount of required threat isn't intrinsically good or bad. Some situations benefit more from one effect over the other (although personally I like increasing the amount of threat required). Although this statement is mostly true for only Solo play.
- This can be played in Alter-Ego form. Which is solid.
Assuming you are playing this card primarily in solo, it's crucially effective against the following schemes:
- Rhino's singular scheme, The Break-In! Even if you're kicking butt and keeping 0 threat on Rhino's scheme, it's definitely possible for him to shoot up to 7 in one go thanks to cards like Advance popping up while in Alter-Ego form. Raising the roof of his scheme to 11 all but guarantees he cannot go from 0 to 11 in one turn except in a supremely unlucky Heroic Expert Rhino game.
- Ultron's final scheme, Countdown to Oblivion. Threat cannot be removed from this scheme, so it effectively sets a 3 turn timer, however; by increasing the required amount of threat instead - you more than double the amount of time you have to complete the game.
While my explanation of the value in using Under Surveillance on Rhino's scheme can be applied to nearly every scheme in the game (preventing it from going 0 to 100 in one turn); I believe the above two schemes in particular are by-far the most noteworthy problems in solo play.
I think this card is a pretty good specific addition to Iron Man decks; it has the energy resource symbol, and Tony Stark likes to stay in Alter-Ego for a while. Any other Alter-Ego focused hero will likely also run it in their justice decks. It's also okay in a deck like Captain America since you can pitch the card for Cap's hero action in the event you already have one in play.
Would I run this card in Multiplayer? For now, yeah. As more options are added to Justice, the odds of including this in MP shrink. 3 cost for 4 effective threat mitigation is still pretty nice. That being said, two copies of this in a solo justice deck are pretty gucci. With three copies, I'd be concerned with drawing them faster than I can apply them to main schemes (provided the previous main scheme has advanced, thus discarding the first copy of Under Surveillance).