These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
For much of the game, a single Barrier Girl in the hands of a skilled player can take out hundreds of opponents, and in the endgame a Beam Gunner can finish a level solo.
The Death Saucer, a borg which costs only 1000 GF energy, can pretty much beat the entire game minus the final boss by using it in every fight and tapping the B button. It has an obscene amount of health and sports tracking, auto-targeting lasers that are strong, difficult to dodge, and recharge quickly, meaning you can keep an enemy stunned until it simply dies.
Neo G Red, being the upgraded form of the main character, is pretty powerful for a measly amount of GF Energy. Amazing melee capabilities along with incredible range make a powerful dual-function Borg whose only real problem is...not a lot of defensive options.
While not unlockable by normal means, only by a long-gone event or an exploit, G Black is effectively G Red on steroids.
The Load: Aside from the in-game example Kotaro, every ally can be considered this. They usually attack the same enemy that you're attacking. It seems tactically sound in theory, but what ends up happening is that you'll either keep getting interrupted by ally when you're trying to attack in melee, or your ally keeps getting in your way when you're trying to attack from range. Even more annoying if your ally is a Pop Honey or Ice Valkyrie. There's also some strange behavior where if your ally is using a character that buffs, they should only use the buffing move on their ally, but they also tend to use normal attack moves as well. Both the enemy CPU and ally CPU does this.
Mana is a bit of a subversion, while she has very limited fire power, she can heal your Borgs back to full health, which could be a life saver in some of the tougher battles, the unfortunate side is that she can accidentally heal the enemy back up to full health.
This troper has done some experiments that seems to show that you need the final hit on a borg in order to get a chance to unlock it. If this is true, then the ally CPU steals kills all the time, denying you a chance to unlock that borg.
The Scrappy: FUCK YOU KOTARO NOBODY WANTS YOUR WHINY ASS COMING ALONG WHY THE HELL DO YOU HAVE SO FEW BORGS IN THE FIRST PLACE AND WHY DO YOU ALWAYS LEAP HEADFIRST INTO COMBAT DESPITE YOUR FUCKING RANGED BORGS AND AND ANDAAAUUUUUGGGGHHHHH
Goddammit Kitsune, your Magnet Robots are not helping.
Goddammit Yuji, get your Jelly Diver away from me!
Usagi will occasionally, when using a Quick Valkyrie, pelt you with shots before unleashing a Haste spell on you.
If you bring melee specialists in a fight with Tsutomu as your partner, expect to periodically get hit with a tank bombardment.
That One Attack: The Galactic Emperor'sRoboteching lasers it fires when only a third of it's health is remaining. These are pretty much all range attacks that can hit you anywhere. They can even hit you when you are directly beneath it.
Orochi is female - actually mentioned early in game in passing and in the manual, but most people miss it.
It becomes more obvious at the end of the game, after she's released from her mind control.
Met. Concept art and fan art more befitting of a girl, but the voice is either a very masculine girl, or a guy. Never referred to in the game or instruction manual as a guy or girl. The baggy clothes concealing the figure don't help.