Fiona is a UR Missile Vehicle damage dealer in Last War: Survival built around Physical Damage and pressure across the full enemy formation. Her biggest strength comes from Atomic Blast, while Double Trajectory supplies steady damage between Tactic cycles and Ballistic Boost improves her Physical Damage throughout the fight. She becomes much more dangerous once her Season 5 Exclusive Weapon enters the build, adding Radiation, enemy buff removal, and eventually a squad-wide bonus for Missile heroes.
The main challenge with a Fiona build is not deciding whether more upgrades are good. It is deciding which upgrades deserve limited Skill Medals, Upgrade Ore, gear materials, and Exclusive Weapon Shards first. For most accounts, the efficient route is to develop her main Tactic before spreading resources across the rest of her kit, build offensive gear before chasing excessive durability, and protect her behind a proper frontline rather than trying to compensate for bad positioning with expensive defensive upgrades.
What Is the Best Fiona Build in Last War: Survival?
The best Fiona build treats her as a protected back-row attacker rather than a self-sufficient carry. Atomic Blast should receive the first major share of Skill Medals, followed by Double Trajectory and then Ballistic Boost. Her regular equipment should lean toward offensive pieces first, while her Exclusive Weapon becomes increasingly important once she is established as a permanent member of a Missile squad.
| Build Area | Recommended Priority | Main Goal |
|---|---|---|
| Skills | Atomic Blast → Double Trajectory → Ballistic Boost | Maximize full-team burst before secondary damage |
| Expertise | Super Sensing separately | Improve Attack, durability, and cooldown rate |
| Gear | Weapon → Data Chip → Radar → Armor | Build damage first while keeping enough survival |
| Position | Back Row | Keep Fiona alive through multiple Tactic cycles |
| Core Missile Team | Adam + McGregor + Fiona + Tesla + Swift | Combine frontline protection with full Missile synergy |
| Exclusive Weapon | Activate → Lv.10 → Lv.20 → Lv.30 later | Add Radiation, dispel, and squad-wide Missile bonuses |
This order also avoids one of the most expensive mistakes in Last War: trying to finish every system at once. A slightly stronger passive, another defensive gear level, or a high Exclusive Weapon breakpoint can all improve Fiona, but those upgrades lose value if her main damage skill or the heroes protecting her are still significantly behind.
What Is Fiona's Best Skill Upgrade Priority?
Fiona's normal Skill Medal priority is Atomic Blast first, Double Trajectory second, and Ballistic Boost third. Super Sensing should be treated separately because it belongs to Expertise progression rather than the same normal Skill Medal path. This distinction matters when planning resources, since trying to place all four abilities into one simple upgrade sequence gives a misleading picture of how Fiona actually develops.
Why Should Atomic Blast Come First?
Atomic Blast defines Fiona's role because it attacks the entire opposing formation with Physical Damage. Improving the Tactic first raises the part of her kit that has the greatest influence when several enemy heroes are still alive, which is exactly where her damage profile differs from a more narrowly focused attacker. Since normal battles handle Tactic activation automatically, there is no need to save or manually time the skill; the important part is keeping Fiona alive long enough to cast it repeatedly.
Why Is Double Trajectory the Second Priority?
Double Trajectory supplies Fiona's regular damage while Atomic Blast is between activations, making it the logical second investment. It becomes even more relevant after her Exclusive Weapon is activated because the upgraded interaction allows her auto attacks to apply Radiation. That means investment in Double Trajectory is not merely improving filler damage—the skill eventually becomes part of the mechanic that links Fiona's personal damage to her full Missile formation.
When Should You Upgrade Ballistic Boost?
Ballistic Boost increases Fiona's Physical Damage throughout battle, so it should not be ignored just because it sits third in the priority order. The better approach is to keep it reasonably developed while the first two skills move ahead. When the next Atomic Blast or Double Trajectory level becomes expensive, a cheaper Ballistic Boost upgrade can offer good value without consuming the medals needed for your next major damage milestone.
- First: Push Atomic Blast toward your next practical skill milestone.
- Second: Keep Double Trajectory close enough that Fiona's regular damage does not fall far behind.
- Third: Add Ballistic Boost levels when the cost is efficient instead of leaving the passive severely underbuilt.
- Separately: Continue Super Sensing through Expertise progression as those materials become available.
A useful guideline is to keep Double Trajectory roughly one upgrade step behind Atomic Blast and Ballistic Boost another step behind when resources are tight. This does not need to become a rigid five-level formula. Upgrade costs change as progression continues, so the better decision is the one that strengthens Fiona's main damage without draining the medal stock needed by the rest of the squad.
What Is the Best Gear for Fiona?
Fiona should normally receive offensive gear before heavy defensive investment. Her weapon slot gives the most direct support to her Attack-based Physical Damage, while the Data Chip is the next piece to develop for offensive performance. Radar and Armor remain important, but their main job is keeping a back-row Fiona alive rather than turning her into a frontline hero.
The exception is a Fiona who repeatedly dies before getting enough Atomic Blast cycles. In that situation, moving Radar ahead of the next Data Chip upgrade can produce more real damage than another small offensive increase, because surviving for an extra Tactic cast matters more than improving numbers on a hero who has already been defeated.
| Gear Slot | Practical Build | Long-Term Target |
|---|---|---|
| Weapon | M3 Turret Lv.20 | M5-A Thor Railgun Lv.40 |
| Data Chip | M3 Data Chip Lv.20 | M5-A Hunter Data Chip Lv.40 |
| Radar | M4-A Seahawk Radar Lv.30 | M6-A Aegis Radar Lv.40 |
| Armor | M4-A Porcupine Armor Lv.30 | M6-A Storm Fury Nano Armor Lv.40 |
| Exclusive Weapon | Lv.1 Activation | Lv.10+ before expensive late investment |
The long-term column should be viewed as a destination, not the entry requirement for using Fiona. Pushing every item toward Level 40 while Adam, McGregor, Tesla, or another core squad member remains badly undergeared usually produces a weaker formation than distributing resources around the pieces that actually determine whether the team functions. Fiona deserves strong offensive equipment when she is one of your main carries, but the frontline still needs enough investment to buy her time.
What Is the Best Fiona Missile Team?
Fiona's cleanest long-term formation uses Adam and McGregor in the front row, with Fiona, Tesla, and Swift in the back row. Adam and McGregor absorb pressure while the three attackers work behind them, giving Fiona the protection she needs to cycle Atomic Blast and continue applying damage. The five-Missile structure also becomes increasingly useful once Exclusive Weapon mechanics start scaling with the number of Missile Vehicle heroes in the squad.
| Position | Hero | Role in the Formation |
|---|---|---|
| Front Row | Adam | Frontline protection |
| Front Row | McGregor | Second defensive anchor |
| Back Row | Fiona | Full-team Physical Damage and Radiation |
| Back Row | Tesla | Missile damage and sustained pressure |
| Back Row | Swift | Additional Missile damage and finishing pressure |
Fiona and Tesla naturally fit together because both become more rewarding as the Missile core matures. Players developing the pair can use the Last War Tesla build guide to coordinate skill, gear, and Exclusive Weapon investment instead of upgrading both attackers independently with no squad-level plan.
Should You Force a Full Missile Team?
Not immediately. If Adam or McGregor is still low-star and poorly equipped, replacing a much stronger Defender purely to activate a cleaner five-Missile setup can make Fiona less effective rather than more effective. A transitional formation can place her behind the two best Defenders already developed on the account, then add another strong damage dealer or Supporter until the Missile roster catches up.
- Keep two heroes capable of holding the frontline instead of exposing Fiona.
- Use your strongest developed secondary attacker rather than forcing an underbuilt Missile hero.
- Move toward five Missile heroes as their stars, skills, and equipment become competitive.
- Avoid distributing Universal Legendary Hero Shards across the entire Missile roster at the same time.
This is especially important for accounts that already invested heavily in a Tank or Aircraft core. Fiona can still add offensive value before the complete Missile lineup is ready, but building a third squad from scratch is expensive. BuffHub's current Last War hero tier list likewise places the dedicated Missile formation behind the safest first Tank investment for most developing accounts, so there is little reason to tear apart a finished primary squad simply to make Fiona's formation look perfect on paper.
Where Should Fiona Be Positioned?
Fiona belongs in the back row in a standard formation. Her job is to survive and continue producing damage through Atomic Blast, Double Trajectory, Ballistic Boost, and later Radiation, none of which benefits from letting her absorb frontline pressure. Moving her forward usually lowers total output because she is more likely to be removed before another important skill cycle.
Extra Radar or Armor can help when enemy damage reaches the back row, but defensive equipment should solve survivability problems rather than redefine her role. If Fiona only survives when she receives every premium defensive item on the account, the more likely problem is an underdeveloped frontline. Strengthening the heroes in front of her can improve both Fiona's damage uptime and the stability of the full squad.
How Does Fiona's Season 5 Exclusive Weapon Work?
Fiona's Exclusive Weapon arrives in Week 1 of Season 5. Activation requires Fiona to be at 5 Stars and uses 50 Fiona-specific Exclusive Weapon Shards. The weapon is important because it does more than provide another set of raw stats: its major breakpoints add Radiation to her regular attacks, enemy buff removal to Atomic Blast, and eventually a direct bonus for every Missile Vehicle hero in her formation.
| Weapon Level | Major Effect | Build Value |
|---|---|---|
| Lv.1 | Double Trajectory applies 1 Radiation stack | Strong activation point and immediate new damage mechanic |
| Lv.10 | Atomic Blast dispels a combined total of 2 hero-applied buff stacks | Major offensive and PvP utility checkpoint |
| Lv.20 | All Missile heroes gain 7.5% Attack, Defense, and HP | Excellent long-term full-Missile milestone |
| Lv.30 | DoT stacks allow Atomic Blast to dispel additional buff stacks, up to 5 | High-investment utility for developed teams |
Why Is Radiation So Important?
Radiation deals Physical Damage equal to 5% of Fiona's Attack every second for 20 seconds. The stack limit on each enemy equals the number of Missile Vehicle heroes in Fiona's squad multiplied by two, with a maximum of ten stacks. This gives a complete five-Missile team access to the full Radiation stack ceiling and creates a direct reason to move from a temporary mixed formation toward the dedicated Missile squad as Fiona's weapon develops.
The key point is that Exclusive Weapon Level 1 already changes how Fiona functions. Unlike a weapon where the first truly defining effect sits behind a much higher breakpoint, Fiona begins applying Radiation as soon as the weapon is active. Players do not need to rush straight to Level 30 just to make the unlock useful.
Why Is Level 10 a Strong Early Target?
At Level 10, Atomic Blast gains the ability to remove a combined total of two stacks of buffs applied by enemy heroes. The eligible effects include categories such as attribute boosts, counterattacks, shields, and resistances, which gives Fiona a second job beyond simply hitting the opposing formation. Against teams that rely heavily on temporary defensive or offensive buffs, removing those effects can change the value of an Atomic Blast even when its direct damage alone would not decide the fight.
Is Exclusive Weapon Level 20 Worth It?
Level 20 is one of Fiona's best long-term breakpoints for a committed Missile account. Missile Specialist increases Attack, Defense, and HP by 7.5% for all Missile Vehicle heroes in battle, so the upgrade stops being Fiona-only investment and begins strengthening Adam, McGregor, Tesla, Swift, and any other Missile hero used in the formation. That squad-wide benefit makes Level 20 much easier to justify once the five-Missile core is properly developed.
Level 30 is more specialized. DoT Exploitation allows Fiona's Tactic to remove an additional buff stack for every 20 DoT stacks across all enemies, up to five buff stacks. The effect has a high ceiling, but it makes more sense after the rest of the formation has reached the upgrades it needs; forcing one expensive Level 30 weapon while another key hero remains unfinished can leave the team less balanced than simply stopping at Level 20 for a while.
What Should You Upgrade First on Fiona?
For a developing account, Fiona's progression should move through useful checkpoints instead of chasing a finished screenshot build immediately. Her Tactic and regular attack establish the damage foundation, offensive gear supports both, and the Exclusive Weapon adds much more value after she is already capable of staying alive and producing meaningful damage. The final stages should be reserved for accounts where Fiona has become a permanent part of the main or secondary competitive squad.
- Build Atomic Blast first with the largest share of Skill Medals.
- Develop Double Trajectory so her damage between Tactic cycles remains competitive.
- Raise Ballistic Boost without letting it consume resources needed for the first two skills.
- Upgrade the weapon and Data Chip before pouring excessive resources into both defensive gear pieces.
- Activate Fiona's Exclusive Weapon once the 5-Star and shard requirements are met.
- Work toward Level 10 for the Atomic Blast dispel effect.
- Aim for Level 20 if Fiona belongs to a long-term Missile squad.
- Consider Level 30 later after the rest of the core lineup no longer has more urgent upgrades.
This order is intentionally squad-aware. Maxing Fiona while Adam and McGregor cannot protect her, or while Tesla and Swift are several major progression steps behind, can produce impressive individual stats without creating the strongest possible formation. Once her core build is functional, compare the next Fiona upgrade with what the same resources could accomplish elsewhere before committing.
Common Fiona Build Mistakes
- Putting Fiona in the front row: she needs time for repeated Tactic and Radiation cycles, not early incoming pressure.
- Upgrading every skill equally: Atomic Blast has a clearer early impact than spreading Skill Medals evenly.
- Treating Super Sensing as a normal Skill Medal skill: its Expertise progression is separate.
- Ignoring survivability completely: offensive gear loses value when Fiona is eliminated before another Atomic Blast.
- Overbuilding defensive gear: Fiona should not consume premium frontline equipment just to compensate for weak Defenders.
- Forcing five Missile heroes too early: a strong mixed formation can outperform an unfinished dedicated Missile squad.
- Rushing Exclusive Weapon Level 30: Levels 1, 10, and 20 already provide meaningful checkpoints before the highest-cost stage.
The broader pattern behind these mistakes is overinvestment in one visible upgrade while ignoring how Fiona actually produces damage. Her best results come from enough frontline survival, strong core skills, offensive equipment, and a Missile roster that can exploit her weapon mechanics. Raising one category far beyond the rest usually creates diminishing returns.
Is Fiona Worth Building?
Fiona is an excellent long-term project for players who intend to develop Missile Vehicle teams. Atomic Blast gives her clear multi-target pressure, while her Exclusive Weapon adds a damage-over-time mechanic, enemy buff removal, and a full-Missile stat bonus at Level 20. Those mechanics reinforce the same formation instead of pulling her build in different directions, which gives a developed Fiona a well-defined place in the Missile core.
She is less urgent for an account whose first strong formation is still incomplete. Building Fiona properly means finding Skill Medals, strong offensive equipment, stars, Exclusive Weapon materials, and enough resources for the Defenders and other attackers around her. If Kimberly, DVA, Williams, Tesla, or another established core hero is still missing an important upgrade, finishing that foundation may offer more immediate account-wide value than pushing Fiona toward an expensive late-game breakpoint.
Fiona Build FAQ
What is the best Fiona skill priority in Last War: Survival?
Upgrade Atomic Blast first, followed by Double Trajectory and then Ballistic Boost. Super Sensing belongs to separate Expertise progression rather than the normal Skill Medal order.
What gear should Fiona upgrade first?
Prioritize her weapon first and Data Chip second because Fiona is primarily a damage dealer. Radar should move higher if she is consistently dying before completing enough Atomic Blast cycles, while Armor normally remains the lower regular gear priority.
What is the best Missile team for Fiona?
The natural five-Missile formation uses Adam and McGregor in front with Fiona, Tesla, and Swift in the back. Do not force the lineup before those heroes are properly developed, since two stronger off-type Defenders can protect Fiona better during the transition.
What Exclusive Weapon level should Fiona aim for?
Activation at Level 1 is already valuable because it introduces Radiation, while Level 10 adds Atomic Blast buff removal. Level 20 is the stronger long-term target for dedicated Missile teams because Missile Specialist grants all Missile Vehicle heroes 7.5% more Attack, Defense, and HP; Level 30 is better saved for a highly developed formation.
Does Fiona need a full Missile squad?
No. She can function behind strong Defenders in a mixed formation while the Missile roster is still being built. A five-Missile team becomes more attractive later because her Radiation stack ceiling scales with the number of Missile heroes and her Level 20 Exclusive Weapon directly strengthens the entire Missile formation.
