A super interesting twist on threat removal for protection. It plays a lot like Hard to Ignore but with the ability to target a side scheme instead of the main scheme. Its fundamental problem though is that when most side schemes come out, you want to clear them ASAP to avoid the negative icons or abilities in the next villain phase. Containment strategy can provide efficient threat removal, possibly 4-6 for only 2 resources, but likely over a few turns. In multiplayer, you'll have better opportunity to clear a scheme before its harmful effect is realized. Ultimately I view this as a scenario-dependent card where I need to know there are side schemes with at least 4 (possibly 3) threat that can be allowed to live a turn or two in play.

The best mode of this card IMO is with player side schemes. So far, they have no negative effect while in play, so you can stick this on one (especially in multi-player, when it will have a high starting threat), and let it chip away throughout the game until you defeat it. This is especially true for the campaign side schemes in Next Evolution like Mission Prep, which come in with very high starting threat but could easily be cleared by a single copy of Containment Strategy.