Pretty easy game actually. If you never spend any money on life, you can get lvl 4 dmg and lvl 4 fire-rate upgrade before first miniboss + double-fire right after him, negating the buff on the normal ships, making that wave easy, and right after the 2nd miniboss = tripple fire - again rendering the buff of the ships useless in comparison. just before the end-boss, one can finish all dmg/rate/health(lol for what?) upgrades then easily.
btw - notice that dmg upgrade and fire-rate upgrade always costs the same on each lvl, but dmg upgrades have a better DMGperSEC/money efficiency. (same with double/tripple shot right after dmg4, rate4 -> 8100 + 8100 for small dmg-boots != 20k for double dmg/sec)
just great: ||R|1,19,218,-64,1,12,380,-124,1,154,426,160,1,242,318,156,1,364,314,-152,1,497,299,144,2,3,4,0||199,86,103,53,144,240,p,25,124,223,50,114,312,114.5,199,26,48,p,164,14,36,46,324,425,114,254,31,123,p,0,0,0,1,416,191,145,90,76,27,p,0,0,0,1|387.45|403.3|391|401||
I prefer this version over the other 2 as story mode, but I'd mix C and B a bit, by adding a 'skip dialogue' option.
A as potential as competive survival bonus level :)
Buzusm > in lvl 21 you have to hit the tail of the worm about .... 8 times per segment, until the worm only has 3 left, then once the robo-worm is outside the planet, give him the final blow :)
it's VERY fun if you never upgrade the sword... you can get like 1000 XP (no joke) from the morning-star tosser in area 3 (just before the last monster) by having 120-ish combos :) ... (even if after 99 you just see the first 2 digits... e.g. 100 -> 10 combo, but still accounts full 100-combo points, and continues to calculate correctly for any more hits beyond that, 110 turns to be 11, and so on...)
@Domrafa - IMO a 6-slot Bowgun is better :D, currently on day 180, with *only* a MK-23 bowgun I crit for ~2k dmg ... and shoot ~5 bolts per second... like a machine-gun. that penetrates. and kills stuff easily. without reloading. (the 3 party members with gravity guns (~2k dmg per hit) and reload ~100 help also, everyone nobles, of course)