An idea for a defensive experimental

[:1]Ok so you have a Dragon a bit like 7 headed hydra only with the body of a giant snake or worm, and very long necks, it normally lives under the ground but when the enemy units get to close it pokes its heads up and burns up or eats the enemy.
It’s best for Defence because it moves really slowly under the ground and when it’s on the surface its very week but very fast its only armour is on its heads and a little down the front of the necks.
Would be good AA as well, it could burn the enemy air units with fire balls or reach its heads up and rip the units out of the sky. |||jazz117|||Man-eating Giant venus fly trap;should have a weakness to fire, but grows more 'mouths' as it gains veterancy, aka as it eats more men and grows. Not specifically a legendary, but a good defensive/guerilla structure i say.|||How about a vine like plant that you summon in an area, which will then attack anything which walks over it, this would be good for choke points or that little bit at the side of your base, that you don't have the resources to defend.|||Wouldnt that be like a wyrm?|||However it manifests, I like this idea.
GPG really need to get creative with their unit design if they want to compete with the rich source material behind Warhammer RTS games and the general ingenuity of (some of) Starcraft II's unit design.
A lot in Starcraft II seems pretty generic, and it is, but they have their little speed boosts and stim packs (Zealots and Marines) and their jump jets and 'blink' teleporting (Reapersand Stalkers) and lots of other cool abilities that make each unit, and the game as a whole, seem unique.
I'm not actually that impressed with the visual design of SCII; I'm just saying, regular fantasy won't cut it.. And even the war boar with a house on its back doesn't feel that unique to me.. Mostly because of its size. If it were 3-10x that size it would be insane. As it is, it's just a giant tank-sized boar-battering ram. It's cool, don't get me wrong, but I hope they have even crazier stuff in the pipeline.
What you're describing here reminds me of Lurkers or SCII zerg units that can burrow then pop-up for an attack.. but if it were done on a massive legendary unit scale, and with hydra heads, then it might really be a unit unlike anything I've ever seen in an RTS. That would be great.