I feel like this is an incredibly powerful card to play when you are first player in a multi-player game - assuming I'm reading this right you would basically beef up all the other players and their allies as well for the entire player phase for a possibly nutso round where you and your allies go twice and every other player does extra damage/thwart. Expensive and less useful in solo.
It’s still very good in solo. If you have 6 allies on the board (which you should be building towards if you’re playing this card) then it’s giving you +6 THW or ATK from your allies and probably 2 THW or ATK from your hero. 4 resources of 8 THW or ATK is efficient. If you combo it with cards like Mighty Avengers and Lead from the Front, then it generates much more value as in addition to the stat boost its giving you a second set of actions boosted by those cards, so could be generating +18 ATK/THW from your allies and +2 ATK/THW from your hero. — Ionichk · 8
Note it is an "event action", so you can play it out of turn...even when not 1st player. — Sluggie · 1