The card Foresight, an Event, says " REACTION : After your Warlord commits to a planet, commit it to a different planet. "

I'm not sure I see where this is useful. Guess I'm being mentally slow here. D'oh!

Also, if you switch it, do your troops follow him too?

The card itself is used between moving the warlord (and any units in your HQ) to the planet you chose with your servo dial and resolving the command struggles. So the event is useful in 2 primary ways:

1) You get to choose where your warlord goes after seeing where your opponent's warlord is. This is very helpful for winning command struggles and for picking which planets have battles - like ones with good planet effects that you can win.

2) The event is part of Starbane's Signature Squad. So the warlord in question committing to a different planet is always going to be Starbane himself. Well, Starbane's effect is " Reaction: After this warlord commits to a planet, exhaust a target non-warlord unit at that planet. " So you commit Starbane to Planet A, use his reaction to exhaust a unit on the other side, play the event to move him to a Planet B, then use his reaction a second time (since you have committed to a second planet) to exhaust a unit on the other side of that planet, too. You have now, probably, ensured that you will win 40% of the command struggles this turn.

When you commit to the second planet using the event, your troops do not follow. The rules on the Command Phase (RRG p. 24) specify that only the units at the HQ follow the warlord - and only when the warlord is committed to a planet from the HQ via the servo dials. The event is used after the warlord and the units are committed to a planet, so it does not invoke/activate those rules for committing from HQ.

Did you pick a planet just to run away from the enemy Warlord but he showed up? Use it to run away. Did you guess wrong and you want to land the killing blow against the enemy Warlord? Chase him down. Or exhaust two units at planets with battles that have Starbane's Council's for massive damage. I've also committed somewhere with one enemy to exhaust him so his Command Icons were ignored and then committed to another for maximum Command wins.

I rarely if ever keep Eldorath at a planet to engage in combat . IF I have initiativie , I pull him back to HQ . If I dont , i have to suffer the hit he will take ( assuming he will be the target of my opponents attack ) and then I pull him back .

Keep him jumping on and off planets all the time to keep his ability useful .

Just a great card. And as ktom said, the best part is that you get to see where your opponent committed himself and can thus react accordingly. Not only screwing up his ability to win command struggles, but also weakening him for possible battles on both planets(there will always be a battle on planet B, of course). If you can pair this with units that have mobility or Wildrider Squadron's combat action, you can win your struggles and rearrange the board for the combat phase. I often use it in some form involving the first planet because you may be able to steal it, if your opponent thought you were more likely to go elsewhere.

You have now, probably, ensured that you will win 40% of the command struggles

Or is that the difference between actions and reactions?

But Im new to the game so please enlighten me.

Reactions do not need action windows. Only the specific event that triggers the card's effect. In Foresight's case, it only needs Eldorath to be committed. Please note that reactions must wait until it's trigger conditions resolve in order to resolve themselves. This differentiates them from interrupts which resolve before the triggering condition.

Or is that the difference between actions and reactions?

Yes, This is the difference between actions and reactions. Actions have to wait for a Player Action window before they can be triggered. But reactions are triggered immediately upon their triggering condition becoming true - and before any other action or game effect can be initiated.

So, since Foresight is a reaction to the warlord being committed, it is used immediately after the warlord is committed and before the next game effect (in this case, resolving the command struggle at the first planet). The event, therefore, moves Starbane before any command struggles are resolved.

It's worth noting that Starbane's own reaction is to him being committed to a planet, so that ALSO should be used before any command struggles are resolved. Using him to exhaust a unit on the other side therefore takes it out of the command struggle as well as for the first round of combat.

Ah thanks for clearing this up. I like this card even more now!