This was an extremely long level and was filled with tough enemies and also massive amounts of bullets, some of them being impossible to dodge. While the player's health bar is sturdy, it is not built to deal with this massive onslaught. The player should prepare to use a continue when the Arbiter-X is reached.
The player must have very good reflexes to dodge the bullets due to their numbers. Even so, the Arbiter-X at the end had a nearly impossible to dodge attack pattern. The player just had to make sure their health bar is as full as possible when they reach there, as up to that point it was possible to dodge all of the bullets if the player's reflexes are very good.
Only choose the multi-directional team. If you choose anything else, it will be near impossible to win because only the multi-directional team has enough firepower to destroy the bosses.
Beating the level using only the Pea Team without any gems spent at all is possible however, but it would be extremely hard. The following strategy uses the multi-directional team, though other teams should also have a similar dodging method.
The Rotobaga should generate enough firepower to defeat the first few zombies. Once you defeat the two Flying Gargantuars coming at the same time, you should gather enough points to upgrade into a Starfruit.
Using other teams, you will only manage to defeat one Flying Gargantuar, which should still be just enough points for getting to the goal later.
Make sure you have full health before reaching the twin Zombie Fighters. If you don't, reset because you'll most likely lose.
Note that their attacks are homed and deal extremely huge damage, so while dodging the red bullets of both the boss and the regular zombies, you should be moving up and down between the gaps to dodge the homed ones from both the regular zombies and Lightning Gun Zombies too.
The fighters have three attacks, one being a quick, small red bullet attack and one being a swirl consisting of yellow, large bullets.
To dodge the first, stay as far as possible, as there is when the bullets slow down and spread out. Go between the gaps of each red-bullet ring. When you realize the rings are too close together, keep yourself furthest from the bullets as much as possible, then concentrate on your ship to go between the small gaps.
When it uses its second attack, also stay as far as possible for a safe spot to carefully watch the pattern. Then quickly but carefully pass through the gaps, which should be big and easy enough. Right before it uses its first attack again, immediately go away from the fighters or you will be hit with the explosion.
Once you defeated one fighter, it's easy, as you would have to pass through one ring at a time. After defeating both fighters, you should be able to gather enough points to upgrade into an Oak Archer.
Midway you should be able to gather enough points to upgrade into an Oak Archer, and then a Coconut Cannon quickly. Coconut Cannon shoots in only one line but it can do massive direct and splash damage and will take care of the regular enemies in seconds.
Then you will see a Double-Cabin Aircraft Zombie. As it has a slow delay before it actually attacks, defeat all the other regular zombies immediately with Coconut Cannon's splash attack.
The Double-Cabin Aircraft Zombie should be easier than the fighters at the start but after a while it will mix the fighter's 2 attacks and will be difficult to dodge.
The first homing blue-bullet attack should be similar to how you deal with the same thing comes from the regular zombies. Immediately go through them before they spread out.
The red-bullet rings will now always come in two and will always be close together. For each pair of rings, go to the gap of the first ring then fly down in a bottom-right direction to easily dodge the second one. The attack is fast however, so you should act quickly.
The yellow-bullet swirl pattern will now also come in two. The method of dodging each pair of curves should be the same as how you dodge the rings, except being much slower and the curves are closer to each other, so be sure to stay focused during the whole attack.
Remember to stay at the top-left if the boss is at the bottom-right, or top-right if the boss is at the bottom-left, or either if the boss is in the middle, to prepare for the transition later. You will be forced to go down to the bottom-right in each curve, so when you realize you are too far from where you are supposed to be, or you are at the bottom of the screen, go up to the upper gap for the next curve.
The transition to the red-bullet rings again will be infuriating, as it happens before the yellow bullets even disappear. Have the least damage taken by preparing yourself standing at the position said above.
After fighting this mid-boss, you should have a bit less than 40% HP left. If your health is even lower than that, then reset, or prepare your gems to pay for revival later on.
After that, regular enemies will appear in masses so watch your step, especially for homing attacks.
Finally you will reach the final boss, the Arbiter-X. With a remaining HP this low, it is possible, but very hard to defeat the Arbiter-X without paying at least 1 continue, so try to kill as much of the accompanying zombies as quick as possible so you only have the Arbiter-X to worry about.
You can only damage some of them during the boss' homing attack, so try to aim your position at the remaining one right after the boss switches places during its red-bullet attack.
Arbiter-X seems easy at first, but then it will make two patterns that are near impossible to dodge. Defeat it as fast as possible before it kills you again. With the Coconut Cannon, you should be able to barely make it.
Unlike the other two, Arbiter-X's red-bullet attack is insane. The rings are shot from two different places of the Arbiter-X, and goes really fast. Immediately get yourself to the left side of the screen, wait until a gap big enough appears, then quickly get through it. Do the same for each ring.
If the accompanying zombies are still there, dodge its homing attack first. As they are grouped closely, they deal much more damage than the boss' red rings.
The next yellow-bullet swirl attack should be similar to the previous bosses, except the position where it is shot from is now different. Do as what you did for the red rings. As this one is much slower, you should not be hit for more than two bullets each time it uses this as it deals pretty serious damage.
After some more blue-bullet attacks will be some curves of yellow bullets that have no gaps between them. These things will cover almost the whole left side of the boss, so make sure to get next to the right of the boss before the bullets spread out.
Now, the next attack is where it gets tricky, as it is nearly impossible to dodge. The attack is basically a maze. Have yourself in the correct starting position, which is the biggest gap of the pattern - the top-left corner. Slowly follows as your gap moves in a counter-clockwise direction. The attack ends with an extremely small gap, so have your ship stay at the exact uppermost part of your screen, then quickly go out and back to the leftmost side to prepare for the red-bullet transition.
The Arbiter-X's bullets do not disappear after its defeat, so watch out for collateral damage.
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