I've been soloing factories for years, even back when it had higher cogs. I use sound (horns) in factories, as well as lure.
Never had too much trouble with it, as long as you spread it out, I would usually throw one in oil room where there are 2 level 5s, and the others on say pipe room. But mainly do use lure
With my drop toon I use sound (horns), then drop the 6's aswell. Lure had missed as much as the sound in my opinion, at the end of the day when game wants to throw in some misses it does regardless of what you do.
I've had factories where missed 3 times in row one set, 2 on another, had to use doodle a little just boost myself for silos, it's just one of those soloing things you have to put up with though.
A lureless factory is more risky but possible, plenty of lureless toons do them. Need to work on with sound and drop, usefull to have doodle with a good tu reliablity (but not essential), and very usefull to have organic drop (which misses less), use drop quickly for best results (or at least this is what i have found).
I beleive best way to minimise getting hit after luring, is to leave the highest cogs till last, and use gag that that will kill cogs without bonus where you can, also if you go for the level 6 cog battles first, gear, boiler and warehouse, you can use the cakes on level 6's that way when don't get bonus jump back it still dies, you then go back to cake can and restock.
As far as catching invasions, you cud use a timer (download one from net, then place outside of TT window), or buy a basic one if you don't play windowed. This way you can have idea of when it is going to end, most invasions are 6-10mins, once you get to 6mins u can weary of it stopping make decision whether to wait it out or try and beat it.
On catching invasions in second busy dists where invasions are less frequent. I usually go side, kill side cogs, oil room, warehouse (clear goons and step on switch even if you use wall shortcut), then clear east and west silos.
Then if no invasion has started then continue to gear room, front, then boiler and pipe. Most of the merits are on silos, so even if one starts before you finish you still get more then risking rest of factory.
By doing silos before the rest of factory, if invasion starts while you fighting in front rooms, you should have plenty of time to finish current battle and get to centre silo before it ends, i found before that with east and west silos to do, i could not be sure i would clear them in time.
Hope some of this helps some people.
'Keep it Kool
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