I accumulated about 120k Workshop cubes and tried full defensive with 100% Block chance, 99% Block, 50% Absorb chance, 150% Absorb percentage and 200% Life steal: http://imgur.com/PjNiHEX
Kinda works, it just takes really long since it's lacking the damage.
And there is a minor bug: if an option like critical hit rate is at 90%, you can still buy 25 upgrades as a pack, totalling in 115% critical hit rate even though the maximum value is 100% (if bought one at a time).
This is a great game. Simple style, yet very addictive.
For upcoming versions, I would like to see auto-updates (player could choose a number of parameters which will be updated automatically as soon as it is affordable) and some option to skip the first 25/50/75/... waves as soon as your permanent updates are strong enough or an auto-skip option like "skip to next wave if living enemies are less than X". Also different movement types (e.g. going in a spiral way) for different enemies would be nice as well as some more stats.
Additionally, I agree with others regarding the balancing. I almost never use any defense upgrades. Even though my tower has only 40 health, I can beat hard mode to level 200 and I just started to play this morning.
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