As the first character to be controlled, Gwendolyn is well-balanced and versatile — perhaps the most versatile of all playable characters. Like Cornelius and Oswald, her weapon makes her a melee fighter; like Velvet, numerous of her offensive Psypher skills (the equivalent of magic) see frequent use due to their usefulness; like Cornelius and Velvet, her skills apply character-specific status effects on her foes: in this case Freeze, for Gwendolyn’s element is ice.
Gwendolyn is the most balanced character when it comes to her physical attacks and her offensive magic, utilizing both POW and PP skills to their fullest. Her spear gives her a wide attack range, and she excels at juggling foes with her combos as well as at crowd control, especially due to the Freeze effect of her powerful and far-reaching ice magic.
As if that weren’t enough, her ultimate attack, Gungnir, is unique among the playable characters in that it hits all foes on the map rather than just those on the current screen.
As a Valkyrie, Gwendolyn is also able to glide in the air, though she can’t stay up infinitely like Mercedes. As expected, she shines in aerial combat, as her skills allow her to lock foes in the air (rather than pushing them around as other characters do), and her damage output while airborne is increased due to the Aerial Force ability.
Gwendolyn may also be the character who profits the most from a measured playstyle, as she is the only character to have access to skills (Pain Feather) and abilities (Counter Guard, Shield Bash, Stun Bash) that reward both dodging and guarding.
It isn’t difficult to get used to the other playable characters that follow, though it may take some time, but it’s hard not to miss playing as Gwendolyn due to her potent magic and her ease in the air, which allow her to easily and elegantly triumph over any kind of adversary (curse you, Frost Ben).
The following is my own advice and recommendations on Gwendolyn’s skills and abilities. Note that these are solely based on my own experience and playstyle as well as forum topics I have browsed; I don’t presume to be all-knowing and to have used all of this in the most efficient way.
All of Gwendolyn’s passives are immensely useful and nicely complement her playstyle, making them worth the Phozon investment in any case. Assault High, Skill Link and Beatdown, while not unique to her skill arsenal, greatly benefit her combo-heavy style. Freeze Enhancement and Icebreaker are particularly great to have in conjunction with her ice magic, which you should make frequent use of.
Gwendolyn’s POW skills play well with her basic attacks: Needle Strike is the one I most frequently use, as it is obtained early and hits multiple foes repeatedly in front of you. I recommend leveling it up as soon as possible. Later on, Rising Crescent is used to launch foes into the air, where you follow up with your combo and benefit from the aerial damage bonus granted by the Aerial Force ability. Beak Drive is used to get behind foes — especially bosses — to dodge attacks and to make use of the Backstab ability, which increases damage from behind. As Rising Crescent and Beak Drive are mostly used for their utility, I don’t prioritize leveling them up.
As for the remaining POW skills: High Trust is, as the skill description says, useful when fighting enemies above you. I never saw much use for Fall Clash though.
Gwendolyn’s core PP skills are Ice Shot, a cost-effective homing spell that applies Freeze and is easily worked into combos, and Icicle Wave and Blizzard, her primary crowd control skills. Blizzard is very powerful, and the Freeze effect can last for a long, long time coupled with the Freeze Enhancement ability. Most of the time, however, you’ll be using the far cheaper Icicle Wave to clear the foes around you. Level up these three skills, especially the two cheaper ones, as soon as possible.
Gungnir is acquired end-game at its max level; while immensely powerful, it is also immensely expensive. I prefer using Blizzard if it can be helped. Needle Storm can’t be used the moment it is learned (the end of Gwendolyn’s book), but is one of my favourite skills: It looks simple and impressive both, is very powerful, and can be worked into her combos, even in the air.
I wasn’t all that impressed with Comet Spear, Freeze Lance and Grid Smash, so I barely used them.
Lastly, Gwendolyn has three support skills: Blinding Light is the “panic skill” that inflicts Dizzy on all nearby foes. It’s useful, but considering how great Gwendolyn’s ice magic is at crowd control, the PP and Phozons are better spent elsewhere. (It’s a different story for Mercedes, who has a similar skill, but less crowd control.) Arctic Shroud saves your Warmer and Cooler potions, but can be stage-specific, as not all stages feature those status effects; I make use of it late-game, but don’t prioritize leveling it. Pain Feather has to be activated for the low cost of 1 PP, but then kicks in passively whenever you dodge. It sounds very useful, but I can’t attest to it because, to my eternal shame, I rarely make use of dodging in video games.
Unlike skills, there isn’t as much to gain from external input on abilities, as they heavily depend on your own priorities and playstyle. For example, I mostly ignored Gwendolyn’s guard-related abilities because… I barely guard in video games I play. (Just don’t ask me how I survive and perform in games without dodging and guarding much.) The other defensive branch gives you access to Recovery Up and Resistance, which increase HP recovery and decrease the chance of getting hit with status effects; while these are both useful, I vastly prefer getting other abilities first.
For offense, you should definitely prioritize Charge Up and Power Supply, which affect POW recovery. These two abilities are the same across all characters because POW is that important, particularly to keep making combos along with your basic attacks. You’ll also want to get Aerial Force and Backstab for enhanced damage, as you’ll want to engage foes in the air and bosses in particular from behind.
In my first playthrough, I also quickly noticed the value in getting Gourmet early on, which affects not just food you eat from your inventory, but dishes eaten at restaurants. Since the EXP gain from eating is quite massive and you’ll be eating a lot throughout the game, the 20% bonus is significant. Leveling faster means quicker access to more abilities, as Ability Points are obtained from level ups.
In my next playthrough on New Game Plus, I might try to make more use of Icy Grip to see how effective the Freeze effect is, especially since Gwendolyn’s passive skill Icebreaker increases damage against frozen foes — though it is a bit scary to intentionally keep your HP below 30%…