Frodo, Sauron’s Bane  W
Legendary Creature - Halfling Citizen
W/B W/B: If Frodo, Sauron’s Bane is a Citizen, it becomes a Halfling Scout with base power and toughness 2/3 and lifelink.
BBB: If Frodo is a Scout, it becomes a Halfling Rogue with “Whenever this creature deals combat damage to a player, that player loses the game if the Ring has tempted you four or more times this game. Otherwise, the Ring tempts you.”
This is a very interesting pick for a commander that utilizes the most enticing mechanic from Tales of Middle Earth. The Ring tempting you, as a mechanic, is powerful in repetition. But how often can you get it going in White/Black?
This Frodo, by himself, can have the Ring tempt you, though it’s difficult to do. Otherwise, there are 19 other cards that can go in a deck with Sauron’s Bane as the commander that can cause the Ring to tempt you. Of these, three of them are repeatable (though Witch-king of Angmar only tempts you when you take combat damage), and one of them is Nazgul, which you can have nine of in your deck and tempts you when it ETB’s. As for the other one-off Ring tempting effects, you have such options as a flicker effect, kill spells, some graveyard retrieval, a mana rock, and a delayed boardwipe.
So overall, it’s not impossible to get to stage four of the Ring tempting you. So how do you get Frodo in? Well the Ring’s first mode prevents creatures with greater power than the Ring-bearer from blocking, but there’s plenty more that can be done. For example, also new to this set (and a card I’ll talk about later), Bilbo’s Ring, makes the equipped creature unblockable and gives it Hexproof during you turn, and only an equip cost of 1 for Halflings like Frodo. Additionally, The Black Gate can make it so that if you’re attacking the player with the highest life total, they can’t block your creatures. Access Tunnel, Manifold Key, Prowler’s Helm, Rogue’s Passage, Suspicious Bookcase, Thieves’ Tools, and Whispersilk Cloak are all also good cards for making Frodo unblockable.
And since you’re making Frodo difficult to block anyway, let’s give him some equipment that gives you some bonuses when you hit with them. Dowsing Dagger, Mask of Memory, Quietus Spike, Rogue’s Gloves, Umezawa’s Jitte, Vorpal Sword, and Elbrus, the Binding Blade all have triggers that activate when the equipped creature deals combat damage, which Frodo most likely will be.
Overall, Frodo is an interesting commander to build around. It might take some finnicking with the ratios for how many ring tempting cards you’d like. But once you find the ratios you like, it should be a fun deck that may or may not make you a target at the table.