Suggestion time.
Critique time.
Chaos Spire. 6 manarack. Constantly shifting and mutating towering structure, changing between different styles of architectures and sometimes to things that certainly aren't architecture, in the more or less center of our fort. It does multiple things. One, being chaos, it can change what it does to a degree. Two, it projects a chaos order that dampens or nulls order magic in the vicinity. Three, that same aura allows our creations more agility, speed, intelligence, and change speed(for the growths n the Stem's hands, for example). Four, it allows other lacrimas to change what they are, though they're still the same size. Finally, it fucks with the heads of our enemies in the vicinity.
I like the sound of that.
A Living Armory. 5 manarack. Grows any small hand held, and some large, weapons we might desire on a momen's notice.
Also sounds pretty good, although why only weapons?
Two Weapon Trees. Thanks to the Chaos Spire, these can take multiple weapon plat-forms. 8 manarack each. Usually they're arboreal artillery, firing explosive gourds indirectly at far off targets. These can of course, have differenT properties, from incendiary to fungus-air bomb. They can also by Micc Wyle(read: missile) Launchers. Small, suicidal, very fast, flying creatures that can track their targets, might have a shaped charge, shrapnel, etc. Typically weaker than the gourds, but more accurate and there's just plain more of them. Anything else we can really think of for them too, to be honest.
Meh. Why use manarack on them?
A Fire Station. Big bonfire looking thing. Shoot heat rays at stuff. 7 manarack. 'nuff said.
Something like this.
That costs a total of 34, leaving us eight plus Krait's for the smaller weapons, which are easily modifiable thanks to the Spire.
I'd suggest letting Krait design some weapons and such for the fortress, too.
I'd also like it if we could have mundane weapons, too. A couple ballistae would really liven things up, and couldn't be blocked by order, cold, and death magic.