Although it would have been cool to see something truly unique, this attachment will work well. Even in solo play and with access to Unexpected Courage, I'm fine with it. Neutral means it's always a viable first turn play, and getting Gandalf action advantage early is definitely worth it.

I can only second this.

To be honest, I find it a bit boring, I hoped Shadowfax would be something really awesome, more interesting, like the Mirror of Galadriel. Of course, the readying effect makes huge thematic sense but the adding of Sentinel and Ranged both lack a bit of creativity imo. I wouldn't know anything really better myself, I think, but Shadowfax needed a bit more flavour imo.

It's a Mearas after all.

I love this card. I always play multiplayer and Gandalf has become one of my regulars. As many of you have already mentioned, this is basically a glorified Unexpected Courage. As UC exists (unforgivingly) only once in the core set, this is a welcome addition to the readying effect mechanics. It's simple but combined with Gandalf's other attachments and his abilities, it can do wonders.