Currently the list is here and is the Bio-Titan Swarm variety.
viewtopic.php?f=21&t=18769Its setup like the AMTL list with each Bio-Titan swarm allowing 2 support formations.
The main Bio-Titan Swarms consist of 2-3 Hierophants, Dominatrix & 2 Hierophants/Hydraphants, 1-2 Hydraphants, 1 Vituperator & 0-2 Harridans, 1 Viragon (Big Trygon) & 0-2 Trygons/Mawlocs.
The support swarms are 3 Hierodules, 1 Hive Tyrant & 3 Carnifex, 3 Lictors, 3 Trygons/Mawlocs, 5 Meiotic Spores, 2 Harridans, Razorfiend/Hive Ship
Also noting that the Hierophant and Hydraphant have weapon choices and can buy Biomorphs
Any Synapse units (Including Bio-Titans with a Synapse Node which can be bought as a biomorph) can buy 2 additional broods (1 Hierodule, 1 Trygon/Mawloc, 1 Tyrannofex, 3 Carnifex)
Essentially its all about swarms using mostly existing background units.
Activations are controlled by placing Hierophants in pairs (2 for 575pts). That leaves the Vituperator as the cheapest and substantially weakest main formation (at 300pts). At 3000pts you're looking at 6-7 individual Hydraphants (400pts base cost, 450pts with 2 Assault Bio-Titan weapons) or 10 Hierophants in 5 formations. Mix and match some cheaper support formations and I'd put the typical activation count at ~10.
The Peak Bio-Titan cost is for the 0-2 Hydraphants acting as Dominatrix bodyguards that can max out at 675pts each (Plus the compulsary Dom at 475pts).
Looking at the 9.2.1 Hydraphant, for the points its 75-100% more resilient than the Warlord Titan and ~50% more resilient than the Great Gargant. Of course the firepower is inferior, it really needs to engage in CC (and against an opposing Titan that does hurt) and it isn't particularly great in a supporting fire role (with a 5+ FF). Its just in a Bio-Titan list it may just grind out results purely on not dying.