The battle with Zeromus on active battle speed 1. Played in real time on VisualBoyAdvance 1.7.2 re-recording v19.3.
Character Levels
Kain Lv58, Rydia Lv55, Cecil Lv58, Rosa Lv56, Edge Lv57
Don't bother healing before approaching Zemus because your party will be restored to full HP/MP before the fight. You should, however, make sure that anything you're going to have Edge throw is near the top of your inventory. You won't want to be scrolling through a bunch of items to find your shuriken because the menus are incredibly laggy in this fight — more so than usual because of the animated background — and it's easy to make mistakes if you're not careful.
After you regain control of your party, Zeromus will just sit there and shake until you have Cecil use the Crystal on him. He won't attack and any attacks against him will fail. But you can have Edge steal a Dark Matter from him which will decrease the power of his Big Bang attack. This is helpful, but unless you get really lucky, it will probably be a while before you manage to steal it.
At the start of the fight, before Rosa needs to start healing, have her cast Haste on herself and, if you have time, on Cecil as well. Zeromus's Black Hole spell will remove it later, but until then, it's very helpful.
Zeromus's main attack is Big Bang, which does around 2,000 damage to the entire party and also causes life drain afterwards. Unless they're near full HP, chances are that Rydia and/or Edge are going to die from it. He can also cast Black Hole to nullify magical effects, so don't bother using any besides the Haste you set up at the start. And when low on HP, Zeromus will sometimes cast Meteor, though it rarely does over 1,000 damage and often misses if your party has decent magic evasion.
As if getting hammered by Big Bang weren't enough, Zeromus also has some nasty counter-attacks. When you hit him with a summon, he'll counter will Bio on the entire party for a few hundred damage each — it's not especially dangerous by itself, but when used directly before Big Bang, it can lead to deaths. If you hit him with black magic, he'll counter with Flare on a single target for around 2,000 damage. Bio is usually the less dangerous of the two, so I recommend sticking with Bahamut rather than casting Flare. And don't even think about casting Meteor or Holy; they're a waste of casting time (Rosa should be healing anyway) and will cause Zeromus to counter with Whirl, bringing one party member below 10 HP where they'll probably die from Big Bang's life drain.
Despite all this, the strategy for fighting Zeromus is fairly straightforward: Hit him with everything you've got and hope your healing can keep up. Attack with Cecil, jump with Kain, throw whatever shuriken you have with Edge and then have him attack, and summon Bahamut with Rydia. Rosa should always cast Curaja after Zeromus uses Big Bang and either top off the party's HP with Curaga/Cura or cast Full-Life to revive someone if she gets a spare turn. If someone is dead and Rosa needs to cast Curaja on her next turn, have someone else use a Phoenix Down first.
Sweet vid, this strategy should help me when I get there, 5 out of 5, oh and by the way, is Zeromus the final boss?
Slither455 3 years ago
Zeromus is the final boss of the main story. But in FFIV Advance the Lunar Ruins, which is an extra bonus dungeon added for the GBA version, opens up after you beat him.
Desbreko 3 years ago
Oh, ok, cool, and does Cid join your party on the US GBA version on the part where you need to save the fire crystal.(Well after you beat the boss there?)
Slither455 3 years ago
Do you mean the Earth Crystal? Cid joins your party when you get the airship from Baron, after which you go take back the Earth Crystal from the Dark Elf.
Desbreko 3 years ago
I give this vid a 3 out of 5 cuz of length. im sure you could have won faster if you leveled up more.
craw111 4 years ago
Well, yeah, I could beat every fight faster if I leveled up. But the point of my videos is to show strategies for beating bosses even at lower levels. Simply leveling until you can win by brute force alone is the easy way out.
For the record, though, I actually beat Zeromus about 20 seconds faster than someone else who was at level 99: watch?v=Y9RrtBK7pOM
Desbreko 4 years ago