My first thought was that this card is only good in a dedicated Victory Display deck, but now I’m thinking about quests that have big non-unique enemies with Victory Points, like the Hill Troll in Journey along the Anduin. Could be really fun to discard a Hill Troll!

This is very much a niche card, and I think that is a good thing (otherwise the Sentry would be borderline OP). However, this ally can really shine in a mono- (or mainly ) Victory Display deck playing across from a more traditional Silvan deck. When you factor in: 1) the discount from O Lórien!, 2) Celeborn's enters play boost, and 3) access to constant healing from Silvan Tracker, the Woodland Sentry is transformed from a prohibitively-costed coaster into a 2-cost Silvan with the potential to nuke a troublesome enemy or location if timed correctly. He can then stick around to quest for 2 (first round), soak up archery, or be bounced back into hand to repeat his ability. Alternatively, you can combo him with Thranduil (imagine taking out a Hill Troll engaged with you before it has the chance to attack!).

The Woodland Sentry may be pretty far down on the list of desirable Silvan allies to play (jockeying for position with Silverlode Archer), but he does have a fun place in the right combination of decks.