I agree with Monstrofocozo about being able to buy random mods (since you can sell them). Using the tactic I mentioned (even before the update), I found myself with alot of money and nothing to do with it. It was pointless buying the other guns when I have no mods to use on them anyway.
Consistent tower placement I've done is (from end point to spawn point): melee > archer > mage > melee (top and bottom row) / cannon (center row) > cannon.
Only thing left to do is to know where to upgrade based on what spawns next. If you know where a "giant" will spawn and you get your hero there, it really shouldn't be an issue.
*Used this tactic before the "target priority" update and it works
Quite easy... I feel that even with the various combinations allowed, you can only really win this game if you focused on using weapons that deal area damage.
If anyone is having a hard time, I started with the Scientist and focused on 20% more earnings until I got that skill to level 6, and that was more than enough to get the henchmen and keep my base repaired. Have one appropriate henchman use the Boomerang Launcher, and the other one use the Sun Gun. For the Scientist, I recommend the Rubber Bomb Launcher. For mods, I would focus on getting Neutrino Barrel, Gravity Accelerator, Quantum Xerox and one mod of your preference (I went with Anti-matter Charge) for the Boomerang Launcher. This one henchman will keep the screen clear until the later rounds.
Why do the upgrade gets less and less useful as you progress down the tree (or atleast the 2nd rank as far as I've seen)? E.g. Sword Training, ALL sword units get +1 atk VS Sword Drill, ONLY sword infantry get +1 atk.
It was okay... adding the other units seemed pointless when all you really had to do was kill off the units that did damage to your castle (goblin, executioner, and basher). Some units made it abit harder (warchief's speed and shaman's heal) but it was just abit. Too easy imo. Battle Expirience (wrong spelling intended :p) > Frost Mastery > Boiled Oil > Burning Fire > Paling ... Then save-up until you can replace Boiled Oil onwards with Accurate Archers without sacrificing Frost Mastery, then go Boiled Oil again.
IMO remove the shield tile. Don't really see any use for it other than wasting space and ultimately, wasting a turn. Bad enough with the small grid without the wasteful tiles.
Basically just stack a booster block and a piercing block on both ends facing the middle (and stack a sticky block on top with 1-2 magma blocks) and sticky blocks in the middle (you can also alternate sticky blocks with grabber blocks but I never saw the need) . Even bosses die to this, and/or replace to digestion blocks once boss is out.
Follow-up on discarding structures - there really shouldn't be a penalty since you already lose 1) the initial structure, 2) any possible cost that you paid for that structure, and 3) the card itself, which is a big loss in any card game.
Easier way to win, upgrade your nuke spell (i.e. ice bolt for water) and your mana pool accordingly, and just continue nuking the enemy summoner. Buy a mage beginner (to regen some of your mana) and another unit for fodder.
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Great! Thank you very much for pointing the effective strategy.