List of Enemies
Enemies do 2x damage in Hard mode, and 0.5x (rounded down) on Easy mode.
Varia Suit reduces damage by 20% (rounded down) and Gravity Suit reduces damage by 50% (rounded down).
| Enemy | Name | Damage (P/V/G) | Health | Power Bombs | Supers | Missiles | Large Health | Small Health | Nothing | Notes |
|---|---|---|---|---|---|---|---|---|---|---|
 |
Acid Worm | 10/8/5 | 600 | 4.88% | 4.88% | 21.88% | 1.95% | 29.30% | 37.11% | |
 |
Acid Worm Spit | 10/8/5 | 1 | 0.00% | 0.00% | 29.30% | 21.88% | 39.06% | 9.77% | |
 |
Atomic | 30/24/15 | 40 | 0.00% | 0.00% | 0.00% | 100% | 0.00% | 0.00% | Lightning does 50/40/25 damage on direct hit, 10/8/5 if you touch the surface where it hit. |
 |
Baristute | 58/46/29 | 200 | 9.77% | 36.13% | 44.34% | 9.77% | 0.00% | 0.00% | Also called big sidehoppers |
 |
Charlie | 50/40/25 | 100 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | Lightning does 50/40/25 damage. |
 |
Charge Worm | 12/9/6 | 60 | 0.00% | 0.00% | 68.36% | 0.00% | 29.30% | 2.34% | |
 |
Charge Worm Spike | 4/3/2 | 1 | 0.00% | 0.00% | 48.83% | 39.06% | 9.77% | 2.34% | |
 |
Desgeega | 30/24/15 | 40 | 0.00% | 0.00% | 48.83% | 39.06% | 9.77% | 2.34% | Also called sidehoppers |
 |
Dragon | 18/14/9 | 18 | 2.93% | 3.91% | 9.77% | 9.77% | 48.83% | 24.80% | |
 |
Dragon Fireball | 8/6/4 | 1 | 0.00% | 0.00% | 19.53% | 9.77% | 29.30% | 41.41% | |
 |
Gadora | 25/20/12 | 60 | 0.00% | 0.00% | 50.00% | 50.00% | 0.00% | 0.00% | Projectile does 30/24/15 damage. |
 |
Gamet | 8/6/4 | 4 | 2.93% | 2.93% | 19.53% | 14.65% | 39.06% | 20.90% | |
 |
Gamet | 16/12/8 | 13 | 5.86% | 6.25% | 24.41% | 39.06% | 24.41% | 0.00% | |
 |
Geega | 8/6/4 | 4 | 0.00% | 0.00% | 29.30% | 9.77% | 48.33% | 12.11% | These geegas appear ONLY in the long zipline room above Acid Worm. |
|
Geega | 8/6/4 | 4 | 4.88% | 9.77% | 39.06% | 43.95% | 2.34% | 0.00% | |
 |
Geruda | 30/24/15 | 40 | 9.77% | 27.34% | 43.36% | 19.53% | 0.00% | 0.00% | |
 |
Geruda | 16/12/8 | 10 | 2.93% | 9.77% | 19.53% | 0.00% | 19.53% | 48.24% | |
 |
Hive | 14/11/7 | 64 | 0.00% | 0.00% | 0.00% | 100% | 0.00% | 0.00% | Only drops health if frozen |
 |
Holtz | 40/32/20 | 30 | 4.88% | 75.59% | 19.53% | 0.00% | 0.00% | 0.00% | Also called owls |
 |
Imago Cocoon | 30/24/15 | 0 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | |
 |
Imago Spore | 20/16/10 | 1 | 0.00% | 0.00% | 39.06% | 9.77% | 0.00% | 51.17% | |
 |
Imago | 10/8/5 | 750 | 0.00% | 0.00% | 75.59% | 24.41% | 0.00% | 0.00% | |
 |
Imago Spike | 20/16/10 | 1 | 0.00% | 0.00% | 80.47% | 0.00% | 19.53% | 0.00% | |
 |
Imago Worm | 20/16/10 | 30 | 0.00% | 0.00% | 0.00% | 58.59% | 41.41% | 0.00% | |
 |
Kraid | 20/16/10 | 300 | 0.00% | 0.00% | 0.00% | 50.00% | 50.00% | 0.00% | |
 |
Kraid's Claws | 4/3/2 | 1 | 0.00% | 0.00% | 48.83% | 19.53% | 19.53% | 12.11% | |
 |
Mecha Missile | 80/64/40 | 4 | 1.95% | 1.95% | 4.88% | 3.91% | 9.77% | 77.54% | |
 |
Mecha Ridley | 150/120/75 | 360 | 0.00% | 0.00% | 0.00% | 100% | 0.00% | 0.00% | Laser does 50/40/25 damage, fireball does 60/48/30 damage. |
 |
Mella | 6/4/3 | 3 | 0.49% | 0.98% | 7.81% | 0.00% | 19.53% | 71.19% | |
 |
Mellow | 5/4/3 | 3 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | |
 |
Metroid | 1/0.25/0.125 | 100 | 0.00% | 12.11% | 48.83% | 39.06% | 0.00% | 0.00% | Damage is per frame, and it is the same on Easy/Normal mode. |
 |
Mother Brain | 20/16/10 | 700 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | Laser does 50/40/25 damage. |
 |
Multiviola | 18/14/9 | 12 | 2.93% | 4.88% | 9.77% | 4.88% | 29.30% | 48.24% | |
 |
Nova | 12/9/6 | 4 | 2.93% | 2.93% | 9.77% | 0.00% | 19.53% | 64.84% | |
 |
Nova | 22/17/11 | 12 | 4.88% | 5.86% | 19.53% | 4.88% | 39.06% | 25.78% | |
 |
Polyp | 0 | 20 | 0.00% | 0.00% | 100% | 0.00% | 0.00% | 0.00% | |
 |
Polyp Projectile | 8/6/4 | 1 | 0.49% | 0.49% | 1.95% | 0.49% | 9.77% | 86.82% | |
 |
Ridley | 30/24/15 | 1000 | 0.00% | 19.53% | 31.64% | 48.83% | 0.00% | 0.00% | Body damage. |
 |
Ridley's Tail | 50/40/25 | 1 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | |
 |
Ridley Fireball | 15/12/7 | 1 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | Fireballs shot at the start of the fight |
 |
Ridley Fireball | 30/24/15 | 1 | 0.00% | 3.32% | 82.03% | 9.77% | 4.88% | 0.00% | |
 |
Rinka | 20/16/10 | 7 | 0.00% | 9.77% | 56.05% | 34.18% | 0.00% | 0.00% | |
 |
Rinka | 10/8/5 | 7 | 0.00% | 0.98% | 34.18% | 4.88% | 0.98% | 58.98% | |
|
Rinka | 10/8/5 | 7 | 0.00% | 0.98% | 58.59% | 4.88% | 0.00% | 35.55% | These rinkas look identical to the red ones but have different drop rates. They are found by Mother Brain. |
 |
Rio | 12/9/6 | 16 | 4.88% | 4.88% | 9.77% | 9.77% | 19.53% | 51.17% | |
 |
Rio | 12/9/6 | 20 | 4.88% | 4.88% | 24.41% | 24.41% | 4.88% | 36.52% | Only appear in the long Rio room seen during the escape from Kraid's lair. |
 |
Ripper | 10/8/5 | 20 | 3.91% | 7.81% | 39.06% | 7.81% | 4.88% | 36.52% | |
 |
Ripper | 20/16/10 | 40 | 3.91% | 29.30% | 29.30% | 19.53% | 4.88% | 13.09% | |
 |
Ripper | 2/1/1 | 1 | 0.00% | 0.00% | 0.00% | 50.00% | 50.00% | 0.00% | Only appears in Imago Cocoon's room. Can only be killed by cocoon falling on it. |
 |
Ripper II | 30/24/15 | 30 | 4.88% | 29.30% | 36.52% | 19.53% | 9.77% | 0.00% | |
 |
Sidehopper | 20/16/10 | 30 | 0.00% | 4.88% | 9.77% | 19.53% | 9.77% | 56.05% | |
 |
Skree | 10/8/5 | 3 | 2.93% | 2.93% | 9.77% | 4.88% | 9.77% | 69.73% | |
 |
Skree | 20/16/10 | 8 | 9.77% | 9.77% | 14.65% | 14.65% | 29.30% | 21.88% | |
 |
Skultera | 30/24/15 | 20 | 0.00% | 0.00% | 50.00% | 40.23% | 9.77% | 0.00% | Fish |
 |
Space Pirate | 100/80/50 | 30 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | Shot does 100/80/50 damage. |
 |
Space Pirate | 50/40/25 | 72 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | Shot does 100/80/50 damage. Only vulnerable to Plasma Beam, which doesn't travel through it i.e. uncharged full beam combo only does 6 damage. |
 |
Squeept | 16/12/8 | 8 | 4.88% | 4.88% | 90.23% | 0.00% | 0.00% | 0.00% | |
 |
Turret | 10/8/5 | 1 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | |
 |
Vine | 6/4/3 | 3 | 0.00% | 0.00% | 19.53% | 4.88% | 29.30% | 46.29% | |
 |
Vine | 10/8/5 | 6 | 0.00% | 0.00% | 29.30% | 4.88% | 24.41% | 41.41% | |
 |
Vine | 15/12/7 | 12 | 0.00% | 0.00% | 39.06% | 4.88% | 19.53% | 36.52% | |
 |
Vine | 20/16/10 | 18 | 0.00% | 0.00% | 58.59% | 9.77% | 19.53% | 12.11% | |
 |
Vine | 25/20/12 | 24 | 0.00% | 0.00% | 100% | 0.00% | 0.00% | 0.00% | |
 |
Viola | 16/12/8 | 12 | 2.93% | 4.88% | 19.53% | 1.95% | 19.53% | 51.17% | |
 |
Viola | 30/24/15 | 20 | 4.88% | 9.77% | 19.53% | 9.77% | 29.30% | 26.76% | |
 |
Waver | 12/9/6 | 8 | 1.95% | 1.95% | 4.88% | 3.91% | 9.77% | 77.54% | |
 |
Zeb | 6/4/3 | 2 | 4.88% | 7.81% | 24.41% | 7.81% | 48.83% | 6.25% | |
 |
Zebbo | 10/8/5 | 6 | 2.93% | 9.77% | 19.53% | 19.53% | 39.06% | 9.18% | |
 |
Zebbo | 18/14/9 | 14 | 5.86% | 14.65% | 30.66% | 39.06% | 9.77% | 0.00% | |
 |
Zebetite | 0 | 140 | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 100% | |
 |
Zeela | 20/16/10 | 12 | 1.95% | 1.95% | 7.81% | 11.72% | 1.95% | 74.61% | |
 |
Zeela | 10/8/5 | 6 | 1.95% | 1.95% | 7.81% | 2.93% | 11.72% | 73.63% | |
 |
Zoomer | 10/8/5 | 3 | 4.88% | 4.88% | 21.88% | 1.95% | 29.30% | 37.11% | |
 |
Zoomer | 8/6/4 | 8 | 4.88% | 4.88% | 9.77% | 14.65% | 2.93% | 62.89% | Also called Geemers |
Drop Rates
Adapted from Dragonfangs' guide on SRC: https://www.speedrun.com/mzm/guide/dir80
Practical stuff
The game does a couple of calculations based on the enemy's position, its index in RAM and multiple RNG values to get a number between 1 and 1024 (the calculation is explained in the "Technical Mumbo Jumbo" part if you're actually interested). Controlling this number in any meaningful way is not reasonable in real time, for all practical reasons it is truly random.
This number is then tested against the raw drop rates derived from the table above. To get the raw value, multiply the number in the table by 1024.
If it's bigger than 1024-(rate for power bombs) you get a power bomb drop, otherwise if it's bigger than 1024-(pb rate)-(super rate) you get a super and so on, continuing with Missiles, Large health and Small health. After your drop is decided however, it can transform into something else based on your current resources.
For health(big and small) it does the following checks:
If health is not full: drop normally otherwise, if missiles are not full: drop a missile if both health and missiles are full: drop normally anyway
For everything else, it does the following:
Is the resources in question not full: drop normally otherwise, if health is not full: drop a large health otherwise, as long as you have the item unlocked: drop normally anyway or finally, failing everything else: drop a small health
So when looking at the drop tables, you can (in cases that matter) add both health drop rates to missile drop rate if you're full on health. And if anything else is maxed out, add it to large health drop rate.
Technical Mumbo Jumbo
The game uses two RAM values for the RNG calculation: 0x3000C77 and 0x3000002. I will refer to them as "frame1" and "frame2" respectively in the formula. These change every frame but can also change by invoking random elements (like checking for drops).
The formula starts as follows (% denotes a modulo operation):
((frame1 + 1) % 256 + ((frame2 + 1)/16) + (enemy's index in the list of enemies) + (enemy x position) + (enemy y position)) % 32
the result will then be used as an index to fetch a number from this list, I'll refer to the fetched number as "listRNG": {13, 2, 6, 8, 7, 9, 14, 10, 2, 4, 14, 4, 12, 15, 13, 12, 11, 1, 3, 15, 0, 6, 7, 8, 11, 5, 0, 3, 5, 1, 9, 10}
the calculation continues:
((frame1 + 1) % 256 + (frame2 + 1) + listRNG¤256) % 1024
and the resulting number is compared against the drop rates.
Note that metroids, in order to give two drops, are technically two enemies, with the second one dying at the same time and in the same location as the first one. So the only thing different between the two drops is the enemy index.
Weapon Information
Beam damage is based strictly on how many non-Charge beams you have active, i.e. Long+Ice will do as much damage as Ice+Wave.
Plasma Beam deals damage every frame it is inside an enemy.
| Weapon | Base Damage | Charged | Pseudo-Screw | Cooldown (frames) |
|---|---|---|---|---|
| 0 Beams | 2 | 8 | 8 | 6 |
| 1 Beam | 3 | 12 | 12 | 6 |
| 2 Beams | 4 | 16 | 16 | 6 |
| 3 Beams | 5 | 20 | 20 | 6 |
| 4 Beams | 6 | 24 | 24 | 6 |
| Missile | 20 | - | - | 8 |
| Super Missile | 100 | - | - | 10 |
| Bomb | 8 | - | - | 6 |