spoiler: the last advanced tower u unlock is the tesla x104 lvl 4 artillary and upgrades include supercharged bolts which allow it to hit 1 extra enemy per shot, per upgrade (however there are only 2 ranks of this upgrade) and overcharge which causes it to release a static burst on every shot, damaging all nearby.
@asmodous i worked out that the fire towers are the REAL best tower, you just need to upgrade it. i found that i earnt 75125 gold per range total with 11 fire towers. just re check ur maths
ummm the lvl where u get the sorcerers is really hard especially the boss bit! but other then that its an epic game, good towers and some good lvls! +if u agree
cant wait to see what next update will bring. I hope its beta only at first cus im beta :) and it would be cool to see a larger variety of bricks on my levels :D