best combo (with no achievement points needed): Fireball, Polymorph, Skeleton, Confusion, Soul Jar, and Reaper. They don't even need to all be lvl 3 to do the 12 minutes. just use fireball, polymorph, and soul jar whenever you get the chance. try to aim the soul jar for the most mana instead of killing the enemies. Reaper and Skeleton work really well together, and it's almost invincible with confusion, since enemies do not attack your units while they are confused. This gives you basically infinite frontline defense; your fireballs will continue to do ranged damage, and your polymorph can get rid of any tough opponents with high HP (or priests that block your fireball). Soul jar is for mana maximization. + to keep this alive.
good thing I'm an expert mechanic that can fix a car no matter how torn up it is (and without using any replacement materials too)....and lucky the zombies don't know that taking away the essential parts of my car, all of which are lying on the open ground, will destroy any hopes of me escaping.
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