What do the game devs consider the best units?

[Gatts]

Griffins:
1. easy to replenish (ressurection, sacrifice works fine + divine armor, armor of the gods etc. - you can buy zounds of them - store them in the spare back up slot and re-fill if you play impossible - still you won't lose any battle)
2. endless retaliation - enemy mostly have many units - more than 5, more than 10, returning attack to most of them gives your unit additional hidden damage ratio (like you would have 5x griffins on the battlefield)
3. split - if you fight many but weak stacks - you may finish them much faster
4. flying
5. natural resistance (not as good as of cyclops, but still good enough)

Vamps:
1. steal life - I never fought army (other than pure undead) that didn't have at least one "living" stack.
2. flying
3. cheap and plenty of them to up-hire in back up stack (for battles with undeads - where the steal life is not working)
4. mind immune
5. even if ressurection does not work, still works sacrifice - if you don't have enough money, but you have sacrifice spell - use it on vamps to replenish other vamp stack - the one that lost units can gain them from blood sucking.

For both of these units is very good to know:
gain additional XP by using only these units + armageddon - your XP will grow because you would be "weaker" compared to the neutral stack, but using god armor on griffins + ressurection, or using steal life of vamps - will make you the victor with minimum loses, even if your enemy was ranked "impossible", just imagine how it is to get 11000 xp instead 500 ... each time...

[Zhuangzi]

To use Dragons effectively, you need to pretty much prevent them from being hit. There's no way you can allow them to cop a 2000 damage hit, because half your stack is gone right there.

At the end of my recent game I had 12 Reds, 15 Greens and 9 Blacks, as well as Dryads and Hunters. This is NOT for Demonis. As has been discussed, Dragons suck in Demonis due to Demons having fire resistance. I don't consider Demonis to be late game - I am referring to Haas' Labyrinth/Murock.

Dragons can't be your shock troops (i.e. the one that absorb hits) but they do massive damage if used correctly. With Onslaught and Tactics (and sometimes Haste too) they have full range over the map, which allows you to choose exactly how and where they will attack.

RED DRAGON:

I actually like this guy the best because I prefer his special ability to the Black's. This can be very devastating in certain circumstances. The best circumstance of all was against General Karador and his crystal, all of which can be fried with his special fire attack. You can use Gift to get the ability back, and Glot's Armor or Time Back if you are going to be hit/have been hit. With normal attacks they hit two enemies. This is important. You need to attack the weaker enemy to line up with a strong one. With high initiative, you will fly off next turn before the stronger enemy has a chance to hit you. You can also Heal them fully for 1 point of mana (level 3 Healing) so you needn't lose any if you're careful.

BLACK DRAGON:

Awesome resistance, but high leadership and a slightly less useful special ability (flying fire). This still works when used correctly, but I prefer the Red's ability. The other problem with Blacks is that you can't use Healing on them. So they ARE tanks, but you do need to be careful. Time Back is always useful though if you do lose a unit or two.

GREEN DRAGON:

Some people swear by these but I have yet to grasp how good they can be. I prefer the fire attack, although the Target Capture and Mana Drain are excellent abilities. Someone else can explain how to use these properly.

So basically I used to share the opinion that Dragons were overrated and easily killed. Well, they are easily killed, IF you let them be hit. But the whole point of getting better at this game is that you don't want to be hit. This is where Dryads are so damn useful with their Lullaby and Summon Thorns abilities. They make a perfect complement to a team of Dragons.

[Sherwood]

Well my personal favs are

Elven archers
dryads
emerald dragon
griffons
Evil Beholder
Demons (just the level 4 version)
Royal Snakes
Inquisitors
Archmages
Shamans

[sours]

Strange - in my game red dragons couldnt be phantomed. Maybed I was doing something wrong.