Plasma Field

[etony33]

The Plasma Field seemingly doesn't serve much of a purpose, and it is usually sold shortly after picking it up on Zelan.

It does, in fact, serve a purpose - but not until after you get Elsydeon. If you intend to grind in Vahal Fort, giving Hahn the Plasma Field (Rika or Kyra would work too, though Rika is probably better off with duel Thunder Claws) will mitigate most damage taken from the enemies there, as the Plasma Field protects against Factor 2, thus helping against Flare Shot and (I'm almost certain) enemy attacks from machines as well. Hahn is better off with two shields and using either techniques or (if you're a cheapskate like me) using a Thunder Claw as an item for the weak Tandle-like effect. This also may apply to Kyra - I haven't tested enough to know whether she's better off attacking with two Moon Slashers or not.

I would recommend not opening the Plasma Field chest on Zelan until you need it.

[Doctor Hooves]

It can be useful -- it will greatly lower damage done by Sa Lews' Legeon.

[etony33]

True, but who would equip it in that battle? Rune can't, Wren obviously can't, Chaz will almost certainly have a sword, so I guess you could give it to Rika, but why bother? Legeon is used as a counterattack if somebody attacks physically, and even if Rika has it equipped, the others will take serious damage.

[MrStarbird]

Plasma Field is the most useful shield in the game next to the Power Shield IMO. Speedrunners use this shield a LOT. It stops Dark Force 1's Flareshot damage entirely (Rika or Chaz can have it in that battle, depending on strategy), it is used in a solo Rika strategy vs. the Triplets, plus it also completely negates the Profound Darkness 3's normal attack. Generally at the end this would be given to Kyra or Hahn, depending on who you use.

[etony33]

For my Seth solo run, I used it for the rest of the game except for DF2 and DF3, when I switched to the Reflect Shield. Attacking Sa-Lews to activate the Legeon counter for single digit damage over and over again was quite amusing. After Raja, I'll take it.