Start here. Formation Armadas are three-target fights in the Delta Quadrant. Regular ones open at Ops 26. Rare Formation Armadas, with the Borg Unicomplex as target, need Ops 38 or higher. You need 100 Formation Armada Directives to start one. Daily Goals and store offers give them. Three teams of four Commanders (12 in all) each take one target, and the teams can come from different alliances. All three targets must fall together. When one target's countdown starts, the other targets inherit the same timer, so the teams must coordinate. Wins pay Artifact Tokens and Premium Artifact Tokens for the Artifact Gallery.
These Armadas in Xindi space come in three levels: 53, 56 and 60. A win pays Materials, Ship Parts and Temporal Artifact Shards. You start one with an Uncommon or Rare Xindi Final Weapon Armada Directive. Xindi mission chains, event stores and special offers give these. Each round that the Weapon is not Burning, its damage rises. Every 8th round it fires a super weapon that deals lethal damage to one ship. Assimilate the Weapon before that round starts and the super weapon is disabled. Timing matters more than raw firepower.
These are the main combat challenge of the Maverick loop. They come in Common, Uncommon and Rare, over 13 difficulty levels, for Ops 55 to 80. You need the Warp Dive Building. You get its key from a mission in the Gift section at Ops 55 or higher. Every attempt needs one Interceptor, one Explorer and one Battleship. If one type is missing, the Armada fires a fail-safe that destroys your ships. Bringing two of one type does not work. The Warp Dive Bar building and maxed Maverick research nodes counter this.
Krenim Formations put you against Temporal Dreadnoughts, and the kind you face changes your approach. Charged Temporal Dreadnoughts regenerate hull every round unless the USS Relativity's Anti-Charged Shift ability is active against them. Static Temporal Dreadnoughts raise their Isolytic Damage every round unless the Anti-Static Shift ability is active. Neutral Temporal Dreadnoughts have no phase alignment and do not need the Relativity at all. Starting one costs 100 Krenim Formation Directives from the Department of Temporal Investigations Faction Store. They appear in 20 systems at the edge of the Delta Quadrant, including Vorex Cluster, Finney Expanse and Veltharion. Wins pay Krenim Temporal Wreckage. You exchange it in the DTI Store for Static or Charged bundles. Their value rises with your USS Relativity's tier.
G6 Solo Armadas are fought alone, in Level 61+ systems (including hazardous ones), with a dedicated solo directive. They pay faction ship blueprints, faction credits, refined materials, refined ship parts, Sigma resources, speedups and more directives. Their special prize is Rare Hazard Particles, which only G6 FKR Solo Armadas give. The particles unlock about 15 new nodes in the Hazards section of the G6 combat research tree. The nodes give faster build, research and repair times, better officer stats, more hazard resistance for rare G6 survey ships, and G6 combat bonuses for PvP. They aim to close the gap that made G6 ships look weaker than G5 ships in PvP.
Open Armadas exist only in the Veil. You need Ops 71 or higher and an Armada Control Center above level 50. Upgrading that building past 50 needs Sigma Resources and Epic Armada Tactical Cores, which come from Open Armadas. Find them in the Open Armada tab on the Alliance Combat screen. You can filter by level, rarity and faction. Players from other alliances can join, and you can share details in Veil Chat. They last 20 seconds instead of the usual 5, with a limit of 20 rounds. If the target survives all 20 rounds, the result is a partial victory. Starting costs depend on rarity: 100 Directives for Uncommon, 200 for Rare and 500 for Epic. Directives come from Armada Control Center upgrades and the Open Armada Refinery.