Yoda of Dagobah

Yoda of Dagobah is very much a tactician's piece. He does a lot of different things, and several of them are either completely unique or shared by only one or two other pieces in the game.

First off, he has zeros in both Attack and Damage, and no damaging abilities of any sort. If you're playing a "kill 'em all" game and he's your last piece, you are dead and don't yet know it (if you're playing a Gambit-scored game, Giant Yoda can theoretically still win by stalling tactics and gaining center points).

The most straightforward usage of YoD is as a Force battery. He has the Commander Effect that lets him share Force Points and the completely unprecedented Force Renewal 2. Not a typo, not an imaginary story, this Yoda gains two Force Points every single activation, making him the best Force battery in the game (except for that elitist bit that he can only share with characters that already have Force ratings; Emperor Palpatine cares about everyone, because he's a nice guy). Not content to just share Force in life, this Yoda also has Force Spirit 6, giving one last gift before he shuffles off this mortal terrain map.

Light Tutor is another crazy ability, unprecedented and unique in the game. It makes any allied Rebel character into a tiny Force-user with a whole Force Point of his own (and, moreover, the ability to share Yoda's glorious bounty). Chewbacca, Rebel Hero is a popular choice for this, but Wedge Antilles, with his suite of "I don't die until I fail some saving throws" abilities, makes for an entertaining choice. Personally, I like to give it to the Hoth Trooper with Atgar Cannon, because spending a Force Point can give that thing a 50% increase in speed. Note that any figure affected by Light Tutor is now also subject to Jedi Hunter, which can be a major detriment.
Next, we get to Yoda's "neener, neener" abilities, Force Alter and Force Defense. You can't use Sith Lightning on him, and you can't attack him very well, provided he's still got some Force Points (Force Renewal 2, in case you forgot).

Oh, and Master of the Force 3, did I mention that? It's actually really easy for Yoda to run out of Force Points despite the FR2, just because he has so many ways to spend them, and can spend them up to three times per turn.

Finally, this Yoda's bread-and-butter move is Force Stun. By itself, Force Stun is a basic 50/50 chance (worse against most Force-users, who can reroll the save) to activate a character for the round. It's only extraordinary in this case because it doesn't replace attacks or turn, and Yoda has Master of the Force 3, allowing him to say, "Stun you I do! The save you have made? Stun you again, I do! Another save successful? Stun you I do!" Bear in mind you can make these decisions as you go, so you can keep at the one guy you really want to stun, or, if the dice are on your side, possibly stun three different targets on the same turn (remember that Force Stun uses the standard targeting rules, though, so you might have to move to get a new target).

Yoda of Dagobah is a very cool piece (if oversized compared to the other Yodas), and absolutely worth the points, but is not a piece for new or inexperienced players. His collection of weird abilities and the Force Point decisions that he forces you to make put him firmly in the "difficult to play well" camp, but he's eminently worth it.

Overall rating in 100: 3 (over a third of your squad not being able to damage anything is a tough pill to swallow)
Overall rating in 200: 4.5 (extremely effective, especially if kept on the sidelines to build up some Force first).