barneys shooting zombies?
How many barneys and how many zombies?
HL2 isn't built to withstand huge numbers of highly detailed characters
And Barneys shooting Zombies is
not "Action"
Have 1 barney + player attacked from all sides and directions,
make the zombies bust through walls, rip through doors, fall in from the roof etc:
give the player a shotgun (fun
) - little armour or health,
high contrast lighting in the middle of the "room" light textures in the background - and where the zombies are, total darkness (this gives them a manacing sihlouete)
Give something to fight towards (anything obvious)
That's Action.