You have the power of magic

(From the official description at Cosmic Encounter Online) - You have the power of magic. After encounter pods are launched, you may switch the two pods so that you launch your opponent's pod and your opponent launches your pod. Generally, you may use magic only after you and your opponent both launch an encounter pod, but before the pods are revealed. But if your opponent is the Oracle, you may switch the two pods when your pod has been revealed and the Oracle's pod has been revealed.

What does this mean?  You almost WANT to get crummy pods, 'cuz that's what your opponent will be playing.  You get to use your opponent's pod if you don't like your own, and your opponent gets your lousy pod.  Makes the -4 a useful pod.  Of course, if you play a negotiate ("N") pod and then switch pods with your opponent, you're going to lose whatever you had in your hand since your opponent is going to get consolation, so be a little careful as to when you switch.

Example:  You are offensive player in an encounter.  Your opponent chooses a pod.  You choose to play a negotiate pod.  You then use your power to switch pods with your opponent.  If opponent played an attack (i.e.  number) pod, you win and get a base.  (Opponent gets consolation in this example, though.)  If opponent also played an "N", you negotiate.

After Sorcerer has made the decision to switch pods (and the Sorcerer animation begins), Sorcerer can be zapped.  In such a case, Sorcerer plays its original encounter pod.

Remember one key rule:  Sorcerer is one of those powers that is all about psychology.  It is important to know when to do the unexpected. If you switch every time, your opponents will be able to predict the outcome, and will play encounter pods accordingly.

Consider what is in your hand.  A hand with many "N"s and/or low pods will result in a lot of switches.  However, a hand with lots of high pods will mean that the Sorcerer power is rarely  used.

Closely monitor how many zaps have been played.  Sorcerer becomes almost invincible if both zaps have been played and the zaps are not likely to be available soon through the Pod Source.

Take care playing a negotiate pod.  As noted above, when an "N" pod is switched to the opponent, the opponent will take consolation from you just as if he/she had played the "N" originally.

Try to anticipate your opponent's response.  If you expect the opponent to play a low pod, you may want to avoid switching.  If the opponent has many pods, but has shown a tendency to assume you're going to switch, play a high pod and avoid the switch.

Limit the number of allies you use.  Offensive allies are frequently unneeded, and defensive allies will potentially acquire zaps and other artifacts that can be used against you.

All three of Sorcerer's opponents should preserve zaps as much as possible to use against Sorcerer.

When you are in an encounter against Sorcerer, consider patterns of play that Sorcerer has used.  If Sorcerer shows a tendency to switch regularly, play low and hope Sorcerer continues in that pattern.

If you anticipate losing and have an "N", play it.  Sorcerer may switch pods and may end up playing the "N".

Consider playing an "N" under other circumstances as well.  If Sorcerer doesn't switch pods, you get consolation.  If Sorcerer does switch, you may end up negotiating with Sorcerer.  Be careful, however, in using an "N" when you have lots of desirable pods in your hand, as a switch by Sorcerer may allow you to win the encounter but lose pods through consolation.

You may want to use a zap on Sorcerer even when you are not a main player in an encounter in order to limit Sorcerer's bases.

Pray.  Players who use Sorcerer effectively can be maddening, and are often victorious.

If you're Oracle, pray more.  Sorcerer gets to see both pods before the switch is made.