I'm assuming the ice dragon is not stationary but moves and that the arena is the usual circular type.
Standard Attack: Ranged 800 units. (frosty type animation). However his standard attack should be non-tracking. i.e. it targets an area and the frost flies towards that
area. So it is dodge-able if your hero is moving.
Spell 1 - (Passive) Each of his standard attacks upon impact with the ground
produces an iceberg with 400HP. After 3 seconds if the iceberg is not destroyed it shatters to reveal a
baby dragon which of course will chase the player and attack them.
Baby DragonHas a
passive slow built in on each attack (5% stacking to 25% max). Additionally the baby dragon has it's type set to
illusion, this way you can set items (Zwill Blade I think it's called) that give HP back when you kill a unit to not work on these baby dragons so the boss isn't too easy.
Event 1 - (After performing 5 standard attacks) The dragon performs a
swiping attack either by tail or claw (which ever is easier to animate) that attacks a
cone shape area directly in front of it (300 units range) doing heavy damage to those hit.
Event 2 - (When boss at 70% HP) The dragon walks to the center of the area, charges up a beam and fires at the direction of the player (the dragon cannot move or turn while firing). The beam leaves a deposit of icicles to form a
wall. Since the dragon is in the center of the area this line of icicles forms a wall with length (radius of the arena) stretching from the center to the edge of the arena.
Event 3 - (When boss at 30% HP) The dragon lets out a roar of pain and charges furiously towards the left of the arena, destroying the arena wall revealing a
second arena to the left. Upon the player following through to the next arena, the passage way collapses and blocks the player from reentering.
Cutscene - (Shows the heroes entering the new chamber). From black screen fade in to view a whole chamber of dragon eggs with many elder dragons guarding the eggs and the main boss in the center.
DialogueG: My lord!....
Dragons: Lots of roars~
G:
Run!(Lots of dragons run towards the heroes, the heroes run south into a long corridor)
Corridor - This arena is long shapes like a long gauntlet. Control resumes and you can utilise
overhead text on top of the characters.
G: Run!
(Player proceeds to run south along the corridor, screen shakes to simulate dragons chasing every few seconds)
P: But the dragons?!
G: There are too many here, we can't fight them.
P: There must be something
(Continue
running, all this is player controlled. Note the dragons never actually catch up (or seen), this is the similar effect used in many RPG's where and event is occuring but you can't actually fail it yet.)
As the player runs past some
pillars.
G: Look there, those pillars. We can bury them
P: I'll take the left you take the right
(Dragon appears at the start of the gauntlet and starts moving at a slow pace)
Players are required to make there way down the gauntlet
destroying all the pillars to collapse the cave (A counter on the top right will show how many left to destroy). Along the gauntlet there are dragon eggs that hatch to provide resistance (enemies) to fight. Each pillar destroyed triggers the 'rock falling from ceiling warcraft animation'.
After enough pillars have been destroyed (i.e. at the end of the arena) a cutscene plays showing the crumbling of the cave (similar animations available from standard campaign) and the heroes emerging just before it happens.
[continue on with story]....etc...