kattw: it is because it doesn't speed up the income actually, but cuts the interval between two payout. And it is most notable with oil rigs, because you usually get the xx oil rig and xx of everything achievements, which means oil rig intervals are quartered why every other interval is halved, thus a lot of payouts happen simultaneously. I hope this helps everyone
This is an interesting game, and I didn't found it that hard. There are 2 important things: 1. you can rearrange your previous upgrades and 2. avoiding something which doesn't or just slowly moves (traps, zombies, lasers, electroshock unupgraded) is much easier than avoiding fast(rockets, saws, random electroshocks). And these aren't exactly upgrades but a way to choose how you want the game to be more difficult so you can make it relatively easier or harder for yourself.
Huge nest, 37 glooples left... PLease just don't spawn a razor queen... Razor queen spawns... Damn... Grinder suddenly squashes razor queen, Holy god, thank you! Won't I get an award for that?
I tried this aganist stabbers: since they can spam you because of their range don't close on them with charge but go forward while slashing. if you are close enough just slash until they try to charge, then poke and slash again.
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great thinking there.