Faction: Yuuzhan Vong

Top Pieces to Know:

Yammosk War Coordinator (steal enemy CE, unlimited range for YV CEs and SAs)
Eighth Cortex Shaper (Evade, Retaliatory Attack for Uniques, reinforcement)
Warrior Caste Subcommander (Blast Bug)
Yu-Ne'Shel Priest (+4 to saves)
Supreme Overlord Quorreal (reinforcements)
Nen Yim (Shaper +10, Master Shaper)
Nom Anor (super-stealth, Self-Destruct 20)
Zenoc Quah (+4 Attack, Evade, Shaper +10, Jedi Hatred via Specialization)


Subfactions:
Yuuzhan Vong pilots
Shamed Ones
Voxyn
Peace Brigade


The best Yuuzhan Vong squads usually revolve around either boosting a few Uniques such as Tsavong Lah Warrior Elite and Shedao Shai with the Eighth Cortex Shaper and other shapers/commanders, or giving Blast Bug to a swarm of non-Unique Warriors e.g. Domain Lah Warriors. In the past pairing Nom Anor and Yuuzhan Vong or Fringe characters with Stealth, giving them super-stealth and Self-Destruct 20, has also been a strong combo.

Some squads:
"The Unforce Five"
"Shadow Bugs"
"Cutting the Corde"
"Pure BB NPE"
"A higher caste of warrior"


ATTA/RoS newcomers:
Charat Kraal, Wing Commander is the brand new toy for the YV pilot subfaction, though 2 of the abilities he hands out (Speed 8 and Evade via Squad Maneuver) are ones that pilots can already access more cheaply from the Klatooinian Captain. He also gives Death-Dealer to Unique pilots, encouraging you to bring a few of them along.

The Shamed Pilot is a new option to spam with the Yorik-Et Squad Leader, 2 points cheaper than the Yorik-et Pilot and coming with melee defense and instead of the Yorik-et Pilot's shooter defense. It probably won't supplant the Yorik-et Pilot, but you may run one or more in a pilot squad since they also provide door control. It can also play in a Shamed One squad, though it's less attractive there.

Unforce 5 is definitely Teir 1 as well as Cutting the Corde. Unfortunately, I think blast bugs have been nerfed out of Teir 1 play and nearly out of existence

I think those squads are more like tier 1.5. They suffer from a lack of movement breakers as the farthest you can go is 6 squares and attack or 12 squares and cannon, which is not enough movement/damage for a primarily melee squad. They're also fairly squishy against other melee squads.