I must say that the Call Colossus scroll is the best possible boost to your army early on, and the earliest that you have a CHANCE to get it is in Scarlet.
In Debir, just make sure you pick up both nautical maps: Scarlet and Bolo. Then once you go to Scarlet there is an undefended nautical map which most likely is the Bolo map. Since you already have Bolo, it will generate a random Wanderer Scroll, and if you are lucky it just might be a Call Colossus scroll.
In my impossible paladin game, I actually replayed the game from the start since I discovered that the Bolo map in Scarlet always gave me Call Colossus. First run I only had 1,100 leadership, giving me a possible Ogre or Troll. Since I was playing paladin, was able to concentrate on Glory (and Learning at the same time); with two items that gave +100 and +200 leadership plus no-loss victories I was able to get to 2,000 leadership to get a Red Dragon (see attached screenshot).
I used the tactic above of using my snake eggs and sprouts one at a time to check which creature I got; for the Red Dragon, I used 12 snake eggs and 3 sprouts ONE AT A TIME. Other choices that I had were 2 Ogres, Troll, Ancient Ent, Archdemon, Bone Dragon, Green Dragon and Tirex.
I wanted something with high initiative and speed, and the Green Dragon would have been technically better (in combo with Phantom), but Rusty Anchor gives you one as a reward for a quest, and two level 5 unit types are better than one. Archdemon could not be Healed, and while Tirex self-heal with each kill they didn't combo well morale-wise with the Green Dragon, and I had the blue dragon pet which gave +1 initiative to animals and dragons.
So Red Dragon it became, which works GREAT in making itself more lethal in working towards upgrading the Battle Alchemy medal.
