"The rule of no realm is mine, neither of Gondor nor any other, great or small. But all worthy things that are in peril as the world now stands, those are my care. And for my part, I shall not wholly fail of my task, though Gondor should perish, if anything passes through this night that can still grow fair or bear fruit and flower again in days to come. For I also am a steward. Did you not know?"
Gandalf, Return of the King
I wanted to build a Gondor swarm deck with some of the new cards released in this final cycle. But my previous attempts would often run out of steam due to lack of card draw. Now I found a formula that works for me. Adding Gandalf provides some out of sphere splash, allowing extra card draw with the revelation of the top card. The bonus from Boromir and visionary leadership means that your swarm army will reach a frightening size. Blood of numenor and gondorian fire on Boromir turns him into a good attacker and/or defender. Steward is added to turn the deck into a proper power deck, but it worked decently in a game where I didn't draw any stewards.
Opening hand: Visionary leadership is key. You really want that card. A wizards pipe is good so you can change your top card, revealed by Gandalf. A very good tale and a few allies are also desirable.
Main strategy: Vomit allies on the board. Use A very good tale and Soldier of Gondor to make sure that your board fills up. Go into Valour mode when you see the Pillars of the Kings, when you feel ready to take on all enemies the encounter deck throws at you. Play 0 cost events from the top of the deck and use wizards pipe to play out of sphere cards. Once you have a stable board presence, start building up a voltron Boromir with the various attachments. You can quest for a lot with Faramir and Visionary leadership, and if you don't want to chump block, your Boromir can take quite a lot. It's a fun deck to play.