Current Emulation Errors
The empty squares on the ground in stage 2 that seem to spawn enemies or powerups out of nowhere are meant to be covered by large orange containers, the first of which has a question mark on it (shown here, in my old Shmupmame v3.0 which actually displayed them properly because emulation makes sense). On stage 3, the Raiden pipe walker mites are unshootable in cases where they should be visibly under cover.
Who To Use
The character with the most scoring potential is most likely Mifune. He's the only one able to destroy the asteroid walls in the stage 5 speed rush effectively, as a result of having not only the strongest weapon in the game but also a bomb that's strong enough to partially destroy the opposite wall as well. This is possible because Kaneko wanted to explosively break my hopes and dreams
A demonstration of his power in action can be seen here. This belief is further cemented by the fact that the newly old WR also used Mifune.He does have some other upsides, such as easily pointblank speedkilling several bosses and large enemies. The hardest parts for him are probably stages 3 and 4, where his lack of range often leaves him exposed. In general, the weaker, laser-based ships in this game usually get more shot points from enemies that take tick damage, while the stronger ones do more damage per projectile and have greater "pushing power". Bombs can also be used to grab extra tick points, though again Mifune would usually rather pointblank things.
The other character capable of scoring highly off the asteroid rush is Jean, whose bomb is (just) strong enough to destroy the walls on both sides. He himself cannot consistently break asteroids on his own, meaning that he can't get quite as many points there as Mifune overall. The upside is that most players will probably find him less awkward to use, especially during stage 3 and the loop.
All the other ships are still very usable if you care more about survival, or if you're not confident of reaching stage 5 and want to try out different scoring options in the earlier stages.
Powerup Bonuses and Rank
From what I've noticed, rank is tied directly to how powered up your ship is and only affects bullet speed. This tends to be more noticable with Mifune than the other ships since he has to get closer to everything, though it's still not a huge difference and should not be a deterrent from aiming for max power bonuses (at least during the first loop). Dying resets power/rank and notably unleashes a radial bullet wave that is identical for all ships and roughly equivalent to using a bomb. Four years before Garegga!
Regular shot powerups give a bonus of 1,000 if already maxed, while max powerups will give 3,000. Subweapons don't power up, but picking up the same one repeatedly allows them to be pseudo-chained up to a maximum bonus value of 8,000. While potentially highly lucrative, whether it's worth attempting to maintain this or not is up to you, as it can get very awkward when there are multiple powerups bouncing around at once and Mifune appreciates being able to switch occasionally.
Up to 6 bombs can be held in stock. Beware however, as, in the sort of twist only this game could come up with, trying to obtain any more than that will cause the game to freeze momentarily and then reset. Don't be a hoarder! :V
Barring stage 2, every powerup will drop from the same enemy/formation each time throughout the game, making it easy to know what to expect and where.
Scoring Tricks for Each Stage
Even with the bulk of score now coming from stage 5, there are still many other small opportunities along the way. Every thousand counts in a low-scoring game like this one, and here I'm now taking this opportunity to document all the intricacies that originally attracted me to it so much.
Stage 1
The first boss is invincible during its opening assault and gives out points for being shot. Mifune can easily push it off the screen and out of range before it moves back down. Bombing or suiciding here might be worth it at absolute top level scoring, but you should still be able to consistently get over 20k points just by shooting at close range.
From what I remember, all the random midbosses offer roughly equal scoring potential, aside from the big sailing ship which gives notably less. Might be worth resetting if it's what you see slowly creeping in.
It's best to speedkill the helicoper/tentacle monster with Mifune to trigger the bonus enemy waves that follow it rather than trying to milk it for shot points.
Stage 2
The first section of breakable grey cubes will give out an extra bonus of up to 10,000 depending on how quickly it's completely destroyed, after which extra enemies will start flying out for even more score. The cubes with red circles on top (here and after) will drop a randomly-chosen powerup.
The invisible orange boxes I described earlier will randomly produce either a set of flying ships or ground tanks, or rarely another set of powerups. After this, both sets of grey cubes on each side must be completely destroyed in order to spawn the rainbow paw item. It's the only way to get an extend in the game, and there's one here in both loops. Make sure to nab it before it flies away! The tank-like object in the middle can be pushed up the screen and destroyed, blowing another big hole in the ship, though this doesn't appear to give any particular bonus aside from that.
Up to four helicopters can spawn after the DRAGONFLY door opens if they're beaten quickly enough. The two rear thrusters can be destroyed when they fly past, as can the two arms of the boss.
Stage 3
There's only one variable scoring element in this stage, that being the bomber plane rush half way through. It's important to try and destroy as many of the actual planes as possible since they give a couple thousand points or so each, rather than just the missiles they drop.
Stage 4
Three more planes here, which now drop parachuting mines. Blue carriers will also appear throughout the stage and release large grenades, which award shot points and can be pushed off the screen before they explode (very quickly in Mifune's case). The sheets of rubble mid-way through the stage don't give a lot of score, but are highly durable and can easily get in the way.
In addition to its other attack, the boss will periodically either fire a laser or release a group of pink flying enemies. The latter can be difficult to deal with at the best of times, but can also be milked for score.
Stage 5:
Aim to destroy as many asteroids as you can, since even the small ones can drop items. Try to pointblank the large ships before they start firing their second attack.
The video showing how to destroy the walls in the speed section was linked earlier so I won't explain it again. It's definitely worth practicing this section until you get the hang of it, and planning how you want to use your resources leading up to this point. Mifune can still grab a decent chunk of score while being short a bomb or two, but Jean is very dependent on having a full stock of 6 to break as many rocks as possible in order to remain competitive at the highest level.
Lastly, the stage boss takes tick damage and the main head spawns waves of green ships.
Stage 6:
Only thing to really take note of in the final boss rush scoring-wise is that the second boss has multiple destructible sections.
The Loop
Overall rank is increased slightly in the loop, and the opening 'attack' from the first boss is skipped. While the bosses aren't much harder, the stages themselves are far more threatening due to the fact that now every regular enemy will release a single aimed suicide bullet upon defeat, barring a few cases such as the stage 1 midboss spawns. This makes places like stage 4 and its block rushes particularly nightmarish, not to mention the difficulties it causes Mifune due to his need to get much closer to things to kill them (or else start losing out on chunks of points). Jean definitely has a much better time here, since he's already probably one of the best picks for the second loop and can pick things off from a more comfortable distance.
The Ending
After beating the final boss in the second loop, it will explode instead of flying away. The other ships will join the player on screen, after which the credits will roll and the game will show off one last trick that's very close to my heart... destructible text! Each individual character (including the full stops) can be broken with concentrated fire for 500 points each, but will fly down off the screen after a few seconds. Your ship will be automatically powered up to full (no subweapon) for this segment regardless of what it was at prior. This offers one last boon to Mifune since he can readily get them all, while the opposite end of the power spectrum (Steel) can only hope to get a handful on each screen. Jean can get most of them, but will inevitably miss a few on the larger screens. There are 11 screen that will cycle through, containing a total of 277 characters for a post-game bonus of up to 138,500. The game then ends with a nice closeup of the ship you used and a thank you very much.
With this guide in hand, I hope you too can begin mastering the art of exploding things while they break. ...With fire. Especially rocks.
EDIT: Added some extra info about using Jean.
