Oncoming Swarm

Well, I have been on hiatus from all things Warhammer for the last few weeks thanks to college. But today I've noticed- rumors are trickling in. Whispers of a growing shadow, of an oncoming swarm.
I am of course referring to the rumors that tyranids are set for either December or January, with mixed sources- one even suggesting a two-month release similar to what we saw with Dark Elves, but I'm not putting too much stock into that. ANYWAY!
One thing I saw is that rippers will be getting a new box set made out of plastic, and the post included some information about rippers. The post also included some information about rippers- namely their use at both the beginning and ending of the tyranid invasion. This gave my warhammer-starved mind an idea for a campaign. *Insert groans of my friends and family here.* Whether this campaign would be used to give a fond farewell to fifth edition tyranids, or herald in the sixth is yet to be seen.

Mission 1: The Oncoming Swarm
Armies
Space marines (Blood angels, space wolfs, etc): 500 points, standard army organization +3 free "Tyranid hunters"
Tyranids: Five tyranid warriors equipped with scything talons and deathspitters and five three-base units of Rippers, with no upgrades.


Deployment: 4X4 board
Space marine player deploys first, placing his models anywhere throughout the entire 4X4 board. Yes, he gets the entire board. "Tyranid hunters" Have stat line of a tactical squad sergeant, equipped with a power weapon, bolt gun, bolt pistol, power armor, and frag and krak grenades.
Tyranid starts in reserves, and can enter from any table edge. Tyranid warriors operate as separate units.

Objectives and game length:
Game will last 5-7 turns using random game length
Space Marines win if at least 2 "tyranid hunters" survive.
Tyranids win if at least 2 "tyranid hunters" are killed.

Special rules:
"Tyranid hunters" have preferred enemy tyranids.
Tyranids gain the ability to assault first turn arriving out of reserves, to show their oncoming assault toward the outpost.

Narrative: A small vanguard warned of an impending tyranid attack on this bio-mass rich planet sets up camp to defend against the initial assault of tyranids, praying to the Emperor to survive long enough to receive reinforcements. Luckily, a handful of marines have faced the tyranids before, and know how to fight them. Should these marines survive, they will be able to train the rest to fight them as well. Should they be lost, however, the Hivemind will know this planet will be prepared and waste no time in bearing the full weight of tyranid might against the planet.

Victory benefits:
Space marines win: XD3 units gain preferred enemy tyranids in mission 2 where X is equal to the number of surviving tyranid hunters
Tyranids win: For each slain "tyranid hunter", roll a D3. During mission 2, the army gains 25 times the total dice result in additional points.