I finished up this bad boy the other day. I really like the direction my Tyranids have taken over time. Allow me to walk you through their evolution...
My first Tyranid models were genestealers from the Space Hulk box set. I painted them as they appeared on the box art: pink-ish with a grey-blue carapace. My friend commissioned me to paint his Tyranid army (I did it for free, so not as much of a "commission") and he wanted everything red with a bone colored carapace.
Towards the end of 3rd edition, I want my own Tyranids. I do some scrounging for coloring ideas and hated all the options I saw in the rulebook and in the codex. ...all except for one image. It was a picture of a hormagaunt swarm assaulting some IG. They were purple with black carapace. I love purple. They looked awesome, and I went with that (I later did a search online for Hive-fleet names and found that purple with black carapace was the color-scheme of the "Hive Fleet Harbinger" ... according to Wikipedia, so 'grain of salt' there).
When I started painting my models, I would hate how everything was so dark and unrefined. Some truly wicked features weren't immediately visible. I played around with it a bit and decided that a bright red fade on the face made them look exceptionally vicious. I loved it. FLUFF: My splinter fleet of Hive Fleet Harbinger had evolved red faces during their separation from the rest of the tattered remains of the broken Hive Fleet Harbinger. On one of the many lush worlds they harvested, there was an indigenous canine with a remarkably sturdy jaw structure offering them a disproportionately powerful bite. Their skin was a bright bloody red. Upon integrating this trait into the fleet's collection of ever-perfecting DNA, in addition to the stronger jaw structure, the fleet's "faces" expressed the bright blood red color that is now all that remains of that particular species.
Fast forward to a month or two ago. We're in 5th edition, and my friend Aernout is painting his Tyranids while I'm painting some Space Marines. Aernout is a ridiculously talented artist (check his deviant art portfolio... you'll see what I mean), and does this great green with teal carapace scheme. He tops it off by adding a bright yellow racing stripe over the top ridge. It was brilliant. I decided shortly after that I liked the idea so much I wanted to use it myself. I asked him first about stealing his idea and after he assured me that I was being silly, I went with it. Orange would be my bright stripe. FLUFF: My splinter-fleet had stumbled across some insectoid recombinant DNA that presented a far more efficient structure for building chitin-based carapace. A poisonous beetle; black carapace with bright orange markings. In integrating it through the fleet, the insectoid's other trait was also expressed; a "warning" pattern appeared on their carapace, similar to that which was on the poisonous insects.
And now we have the state of my current hive fleet. The rest of Hive Fleet Harbinger probably wouldn't recognize them any more, though they are still technically part of said fleet.
The purple parts were all painted with a 2:1 mix of Warlock Purple : Dheneb Stone. It's bright pink. Fix that by hitting it with a healthy dose of Leviathan Purple Wash. Much better. Carapace was Chaos Black with a Codex Grey drybrush. The orange used was Blazing Orange. Bone was painted in Dheneb Stone, washed with Devlan Mud, then drybrushed first with Bleached Bone, then with Skull White. I found drybrushing has a great grainy effect that works wonders on bone/carapace stuff. It looks natural. The green areas (Toxin Sacs and on his Lash Whip) were Rotting Flesh followed by a Thraka Green wash.
The basing is standard GW sand and rocks, followed by a Devlan Mud wash, then a Bubonic Brown drybrush. Here is a sample of the test base I used to figure out what I wanted.
Oh, did I mention he's magnetized?
Above, I've highlighted the locations of all the magnets used - 5 on each side. If you plan to use a similar idea, something I've learned... Make sure the two large magnets have the same property facing outwards. I.E. when you're done making an arm with magnet, you should be able to affix it to either the top slot or the bottom.
The small magnet up on top of the carapace is for the Adrenal Gland (I had to carve that thing up to get it to fit properly. They give you the same one as for the Carnifex, and the Hive Tyrant's carapace peaks at a much more acute angle.
The small magnet between the ribs is where I put the Toxin Sacs. This way I don't have to put them on every arm attachment I have.
The small magnet right above the upper arm slot is for the Extended Carapace.
Below, you can see the model with those three smaller magnet slots occupied with their biomorphs:
Yay for options!