Jarvan IV Demacia Defender 1g

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Jarvan IV is a supportive frontline tank. His Demacian Standard ability grants himself a Shield while also buffing his allies' Attack Speed. He'll definitely be useful in Demacia comps, but could also have decent utility on other boards when dipping into Defender.
Rumble Yordle Defender 1g

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Rumble's Junkyard Titan sets up a Shield before firing a burst of flames, dealing magic damage in a cone. He's a pretty stock standard unit for the early game, but his flames scale with Armor, providing the option to turn defense into offense later.
Neeko Ixtal Arcanist Defender 2g

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Neeko's a great early game pickup thanks to the combined Ixtal, Arcanist, and Defender traits. Having three synergies as a 2-cost is always welcome.
On the battlefield, her Pop Blossom ability has her leap at the target, gaining a Shield before slamming down to deal AoE magic damage. This also applies a Chill, giving her some supporting potential with Freljord units.
Vi Piltover Zaun Defender 2g

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Vi follows up as another 2-cost, three trait champ with Defender, which is once again well above the curve. Her Relentless Force ability Shields, slams an enemy, and deals damage to those within range.
However, best of all, after every third cast she'll also knock up enemies hit, giving her a modest form of CC. Combined with Zaun's huge on/off Attack Speed buff, Vi could put a real dent into those who oppose her.
Darius Noxus Defender 3g

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Darius's Decimate restores health, then spins to deal physical damage to adjacent enemies. This effect also applies a stack of Hemorrhage, causing the foes to take additional damage over time.
In classic Darius fashion, he has the ability to execute Hemorrhaged foes that fall below a certain Health threshold. With Darius, you won't have to worry about them getting away with a sliver.
Kennen Ionia Yordle Defender 3g

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Kennen provides a ton of value for a 3-cost unit. While he does need to be unlocked, it'll come naturally as you invest into either Ionia, Yordle, or Defender, and the reward is worth the effort!
Slicing Maelstrom Shields Kennen as he summons a lightning storm, causing waves of bolts to hit enemies wiithin range. The first three foes hit are also Stunned for 1.5 seconds! AoE Stuns are definitely a premium, making Kennen a fantastic choice.
Sejuani Freljord Defender 3g

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Sejuani's Winter's Wrath Shields and strikes enemies within a cone and a line. This ability deals magic damage, Chills foes, plus Stuns enemies that were previously Chilled.
Alongside other Chill support she has great CC potential, which probably has her lean mostly towards Freljord comps. A solid Defender regardless, but great potential when used to the fullest.
Garen Demacia Defender 4g

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Garen is a simple but strong frontliner that heals and gains Durability in combat, gotta spin to win. Each second of his Judgment deals physical damage to nearby enemies while simultaneously reducing their Armor and Magic Resistance.
This makes Garen a good supporting unit, as he can get into the fray and soften up enemies for your carries. Sometimes simplicity is all you need.
Sylas Chainbreaker Arcanist Defender 7g

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Sylas is a spicy unlockable payoff that requires you to sell a 2-star Jarvan, 2-star Garen, and a 2-star Lux. Doing so grants a fun champion with a plethora of useful abilities.
Stolen Might alternates between casting one of three different spells, supposedly choosing the best fit for the situation (can't cast the same spell twice in a row).
Cataclysm (Jarvan) leaps at a target close by, Stunning them and dealing magic damage to others within range. Demacian Justice (Garen) deals a large burst of damage, executing them if they are low enough Health. Lastly, Final Spark (Lux) grants a Shield before firing at all enemies in a line.
Sylas has a pretty unique cost for a very interesting set of abilities, so we'll have to see how it plays to find out if it's worth the effort. Though if you've been investing into Demacia and it's not working out, Sylas could be a pretty exciting pivot/escape plan.
Thanks for reading! If you want to try and come up with your own team comps for Set 16, check out our Team Builder. For a full overview on the new set, check out our TFT Set 16 Reveal Page.