Level Katrina to 30 whatever else you’re building: her third skill pays fuel and exploration EXP to your whole account every day, whether or not she ever marches.
- Class: DEF
- Faction: Blood Rose (Assaulter troops)
- Rarity: orange (S)
- Arrived: the base roster; she carries no season tag
- In one line: a defender with attack skills and an account-wide exploration bonus
Skill numbers on this page are the level 30 values, which is the cap, read from the game in the Dinosaur Origin season (Season 4 where Desert counts, Season 3 where it doesn’t).
What Katrina does
Katrina is two heroes in one body. In a fight she’s a Blood Rose defender whose combat skills are, oddly for her class, about hitting harder: Explosive Bullet raises the damage of her normal attacks, and All-Out Assault calls the elite troop in for a six-second burst at a damage factor of 2400. Her talent, the skill you unlock late, buffs her own attack, defence and troop capacity at once.
Her third skill is the one most players care about, and it has nothing to do with fighting. Exploration Genius raises the idle EXP your exploration stages earn by half at full level, and from its first star it hands you 100 free fuel a day. The game files it as a Global Effect: it works for the account, not for the squad she’s standing in, which is why she’s worth levelling even on a day you’ve got no plans to field her.
So the question isn’t “is Katrina good?” It’s two questions. Does she hold a place in your Blood Rose line-up, and have you taken her to 30 yet. The second one has only one right answer.
Katrina’s skills and stats
| Skill | Type | Unlocks at | What it does at level 30 | What each star adds |
|---|---|---|---|---|
| Explosive Bullet | Normal Attack Boost | hero level 1 | Increases normal attacks’ damage factor to 1500. | +90, +90, +90, then +120 and +210 to the damage factor |
| All-Out Assault | Active Skill | hero level 20 | Commands the elite troop to unleash full firepower at damage factor 2400, lasting 6 seconds. | +150 damage factor, duration +1 second, +150 damage factor, a fourth bonus to the assault, then +300 damage factor |
| Exploration Genius | Global Effect | hero level 30 | Idle EXP in exploration stages increases by 50%, account-wide. | 100 free fuel a day, idle EXP +5%, idle EXP +5%, fuel restoration speed +10%, then idle EXP +10% |
| Potential Unleashed | Exclusive Talent | hero level 50 and 4 stars | Self ATK +10%, DEF +10% and troop capacity +5%. | The talent itself; no star steps |
Her attack, defence and troop size climb with her level, her stars, her skill levels and her gear, so the live figures are on her hero card in your own game. The thing to know about the base numbers is the rarity gap: an orange hero starts well above a purple one and caps higher, and Katrina is orange.
The upgrade order that gets the most out of her:
- Level her to 30. That unlocks Exploration Genius. Nothing else on this list matters until it’s on.
- Put her first star in. The daily 100 fuel starts there, and it never stops.
- Spend skill books on Exploration Genius next. Every level is more idle EXP for the whole account, up to 50% at the cap.
- Level 50 and four stars for Potential Unleashed, if she fights for you. If she’s an account skill and nothing more, this can wait.
- All-Out Assault, then Explosive Bullet. Both matter only when she’s in the squad.
How to get Katrina fragments
Katrina’s own fragments come through the Bar. A full claim of Prime Recruitment Tickets pays out her fragments, so the tickets you earn and the ones events hand you are the direct route to her stars.
Beyond that, the game pays out orange fragments on a schedule. Most of them are universal and work on any S hero, a few are tied to one hero, so check the item before you count on it. Once she’s unlocked, these are what you’ll be feeding her:
- Daily Tasks. Reaching 150 points on the Daily Tasks page pays one orange fragment.
- Full Preparedness. 18 medals trade for two orange fragments.
- Gold Trucks. Sending and looting them is the steady source most players overlook.
- Weekly gifts. Six orange fragments a week, claimed, not earned.
- The Z Points store sells S fragments five at a time for diamonds. If you’re deciding whether that’s a good use of diamonds, the diamond guide covers what to save them for first.
- VIP 10 adds daily orange fragments, which is a route for spenders rather than a plan.
Four stars is the milestone, because that’s where her talent unlocks.
Best build and gear for Katrina
Hero gear fills four slots: Gun, Helmet, Armor and Boots. The Gun boosts attack. The Helmet boosts attack and defence. Armor boosts defence and troop HP. Boots carry a mix of all three. Gear levels up with enhancement alloys and promotes with power cores, and promotion is where the real stat jumps live, so it’s worth deciding early which hero gets the cores.
Katrina’s class says defender, but read her skills: two of the four are about her own damage output, and her talent buffs attack as much as defence. A build that treats her as a pure wall wastes Explosive Bullet and All-Out Assault. A build that treats her as a glass cannon ignores why she’s classed DEF in the first place.
The order that fits both halves of her:
- Gun first. It scales the normal attacks Explosive Bullet is built on and the burst All-Out Assault delivers.
- Helmet second. Attack and defence in one slot, which is her whole profile.
- Armor third. Troop HP and defence, for the hits a defender takes.
- Boots last. They round her out, but every other slot does more for her.
If you’re short on cores and she’s an account skill rather than a fighter in your game, don’t promote her gear at all. Levels and one star do the job.
Best formation and faction pairing for Katrina
A formation carries five heroes and their troops, and Blood Rose heroes field Assaulters. The reason to build Katrina a Blood Rose squad rather than dropping her into a mixed one is written on two of her faction-mates’ talents. Oliveira’s gives the troop +5% attack and defence for every Blood Rose hero deployed, and +10% troop capacity when all five are Blood Rose. Selena’s gives every Assaulter unit +10% damage whether or not she’s deployed. A full Blood Rose line-up collects all of that; a mixed one leaves most of it on the table.
The faction triangle is the second thing to keep in mind. Wings of Dawn beats Blood Rose, Blood Rose beats Guard of Order, and Guard of Order beats Wings of Dawn: the Season 4 heroes spell it out in their talents, with Queenie’s Wings of Dawn troop dealing extra damage to Assaulters and Amber’s Guard of Order troop taking less from them. A Blood Rose squad with Katrina in it is at its best against Guard of Order and at a disadvantage against Wings of Dawn. The triangle shifts a fight; it doesn’t decide one.
Who to put beside her, keeping the squad Blood Rose:
- Oliveira first. Her talent is the squad bonus itself, and it pays per Blood Rose hero.
- Selena for the Assaulter damage, which her troops and Katrina’s both collect.
- Yu Chan for damage. The Season 4 Blood Rose hero, built to hit.
- Sophia for her attack skills, and she pulls construction duty when she isn’t marching.
That line-up is built on the faction bonuses first and role coverage second. If your Blood Rose roster is thinner than that, keep as many Blood Rose heroes in as you can, since Oliveira’s bonus counts each one, and let Katrina’s talent cover some of the gap.
Is Katrina worth it for F2P?
Yes, and for a reason that costs almost nothing. Exploration Genius is a Global Effect: it works whether she’s in a formation or sitting in the barracks. To switch it on you need her at level 30, and to get the daily 100 fuel you need one star. Both come from play, not from the store. Exploration stages are the chest in front of your HQ, the idle reward that caps at eight hours, and they hand out hero EXP, power cores and equipment boxes, so half again as much EXP there is more of everything.
For a free player, that makes her the cheapest account-wide bonus in the roster you already own. She’s a base-roster hero, her fragments come through the Bar, and the first two steps of her upgrade order are the whole payoff. Everything past that is optional and depends on whether she fights for you.
Katrina vs the alternatives at the same role
| Hero | Faction | Rarity | Where she fits |
|---|---|---|---|
| Katrina | Blood Rose | orange | The defender for a Blood Rose squad, and an account skill on top |
| Miranda | Blood Rose | purple | The same faction’s purple defender. The fallback while Katrina’s stars are low |
| Elizabeth | Guard of Order | purple | The defender for a Guard of Order line-up |
The honest comparison runs on two lines. On rarity, orange beats purple on base power and on ceiling, so Katrina outgrows Miranda as the stars come in. On faction, the squad bonuses are worth more than any one hero, so if your line-up is Guard of Order, Elizabeth keeps them intact and importing Katrina breaks them.
What none of the alternatives offer is her third skill. Even the player who never fields her is levelling her to 30 for the fuel and the EXP, and that’s a reason to own her that no other defender gives you.
Where she lands against the whole roster is on the tier list. For what to do with her in your first day, the beginner’s progression guide covers it.
