I'm in the process of developing a specific scenario to mimic a "last stand" by Space marines. Please review and post feedback on how to make it more balanced. I'm unsure of whether or not giving a VP -v- VP boost to Space Marines (such as 1500 tyranid -v- 1250 space marines) would make it more balanced like they do in Fantasy.
Always considered 'in cover' (4+ cover) while in the bunker.
No Vehicles except Dreadnaughts & 1 Fly support (aka 1 Storm Talon or Landspeeder is ok). No bikes. Total points of Vehicular defense must be 25% or less of army value.
Space Marines will be Fearless but still may fall back if the player chooses.
Space Marines may "Split Fire" (i.e have different weapons select different targets)
Space Marines may still Fire during shooting phase if they are far enough away from combat. I.E. a Tac Squad is assaulted, and after assault still only has 6 guys in Combat and 2 out (2 died). During Space Marine Shooting, the 2 that weren't close enough to fight may instead shoot if they have a valid target.
Space Marines may Reinforce other Squads. (i.e. move tacs from 1 unit to another)
Space Marines may elect to kill special weapons last (presumed 6th ed style)
Board-wide Synapse as long as "Leader" is in Reserve or on table. 1 Hive Tyrant variation must be the leader.
Turn 1: Deploy Swarms/25mm Units
Turn 2: Monstrous Infantry May deploy
Turn 3: Monsters may Deploy
Units taking Mycetic Spores may only come out on turns they would normally be allowed. Not allowed to Deepstrike into bunker.
1 12" x 12" bunker setup so it was a 2 tier bunker. That way Space Marines could fall back to the inner courtyard if neccessary. Bunker will be elevated (on a hill). 25mm could not climb over and must break through choke points. Big Monsters (if they get close enough) may engage over the walls.
Lots of Rocks/Hills from the outskirts, preferably with at least 12" or more of clear space in all directions from the bunker of which the Tyranids must cross.
Space Marines Deploy First & Have First turn. There is no Seize the initiative. Space Marines deploy in center. Tyranid can then deploy on the longs at least 24" away from the bunker. Reinforcements may come in from any side (Longs or shorts)
Tyranid wipes out opposing Space Marines completely. - Major Tyranid Victory
Less than 5 Space Marines make it out alive - Draw
More than 5 Space Marines make it out alive - Major Space Marine Victory