Ok, there have been quite a few Metal Storm runs submitted lately, but here is the first one that plays in expert mode and actually gets the real ending. I put in a password in the beginning which starts me out in the beginning of expert mode with the gravity fireball powerup. To play in expert mode you either need to beat the normal mode or enter a password, so I think this is fair. When entering the password quickly, the letters displayed are not what the game reads. The password I actually used is B10-5(heart)RJ-27V.
The main glitch used allows me to bounce around as a fireball, it's done by hitting jump at the right frame. The same technique also allows me to jump off of spikes, whether or not I have the fireball. If you consider it a glitch, it's possible to hit enemies off-screen. I use this several times, including on the last boss.
In expert mode all enemies take more hits, and there are more of them. Besides that, the distribution of powerups is more sparse. The bosses not only take more hits, but have new attacks or different patterns. The first boss has a homing shot, the second fires more often, the third and fourth move faster. Can't tell much about five. On the sixth boss, each platform takes a different number of hits: 2, 5 and 8. Their vulnerability times are independent, so it's only critical to hit the 8-hit one as soon as it opens up. Note that on boss 5 the right of the room is supposedly spiked, but I hop around on it anyway. On boss 6, the platforms are supposed to be the only safe spots to stand. I don't like following rules. :) The last boss actually has some defense in the form of these fireballs that seem to be flying around randomly. Well, despite all these changes, I'm less than a minute off of any of the submitted normal mode runs. Cheez has posted an 11:43 run in the forums which seems to be about the max for normal mode.
I take a hit on the stage 4 subboss. It kills the last cannon immediately, sacrificing my armor powerup. Since this hit finishes off the fight, the normal animation is skipped. Because the hit animation normally takes so long, it's not worthwhile to use anywhere else. It seems that an armor hit either kills the enemy instantly or does nothing, so it's less useful here than it is in normal mode.
Gravity fireball is extremely powerful, it's without a doubt the fastest way through most of expert mode as it does so much more damage than anything else. However, the sixth boss can only be damaged with shots, and takes twice as many hits without the power gun. Furthermore, he only takes one hit at a time, and the fight is close to a minute even with the power gun. For this reason I need to pick up the power gun in stage 6 and use it for the rest of the game.
When watching this, keep in mind that expert mode is impossibly tough. You may not realize it since I breeze through everything and even have room to showboat quite a bit. For fun, I try to bounce through some levels as a fireball, though other times it's more interesting to show that I've got some moves even when I'm not on fire. After each boss, I have some time to dance. It's tough to do as a clunky robot, but I manage to get a groove on to some extent. Another refinement is not missing any shots. There are a few times it may seem otherwise when I'm hitting something offscreen.
Killing as many enemies as possible isn't just for style, it also helps prevent the horrible slowdown that this game is prone to. This is particularly important when the enemies shoot at you. The gravity fireball is able to cancel out enemy shots, so I do this as well.
Some collaboration between Cheez and myself revealed a few flaws in the first two levels, mostly minor. I'm more confident about the later levels. The biggest improvement would likely be beating boss 1 before his blue thing withdraws. There's maybe 3 seconds of known improvement at the most. It looks like Cheez and I will have a little competition to make the next version. However, we agreed that this run was high enough quality to last timeattack fans until then. Enjoy!