budget lineup

Do you want suggestions on a team for any challenge or a team for Camelot specifically? If it's Camelot, I can't help much, since I haven't started that Singularity yet, but the usual recommendation is to level up your Archer servants, which in your case are Robin Hood and Emiya. Robin Hood is likely more important since he has a single target NP that's better in boss fights.

In terms of a general, non-Camelot team, my recommendation would be: Altria (w/ Seal Designation Enforcer or Limited / Zero Over) + Hans (w/ Divine Banquet) + Fuuma Kotarou (w/ Imaginary Around), with Mash and Heracles (w/ Volumen Hydragyrum) in the backline.

The strategy is a buster crit team: use Fuuma Kotarou to generate stars, Hans to buff the team (his Human Observation skill boosts team critical damage; his NP heals and can apply attack and defense boosts), and use Altria as your main damage dealer. The problem with Altria is that she doesn't have naturally high star absorption or a skill to boost her star absorption, so she'll have trouble taking advantage of the stars that Fuuma is generating -- hence why you may want to use the Seal Designation CE on her. Mash exists to boost team survivability, and Heracles is your "last man" to solo difficult fights. With Volumen Hydragyrum (I'm assuming you don't have his bond CE), his Evade skill, and his Guts skill, he'll have decent survivability for the final turns of a tough battle.

Alternatively, you could try to borrow a Gilgamesh from friend support and use him instead of Altria, but that's tough to do. Your main damage dealer is too important to be left to whoever's available on the friend support screen.

Here is my suggestion , I won't include CE because it is a matter of personal taste and most of the time you will know what you need.

1. In camelot, you need at least one good servants from all class.
Let's start to analyze it one by one :
- Saber : Any 5* is good
- Lancer : Your cu should be enough, it is highly recommended to Max Protection of the wind and Battle Continuation
- Archer : You are severely lacking in this area. Remember that some of the tough bosses (if not all) are Saber class, which mean you need a very good and max leveld Archer. Max your Emiya archer/any good archer you have, then recruit Euryale/Orion as Support to counter those Male bosses.
- Rider : If you can increase Kintoki Rider to 70, that should be enough. Is KintokiRider at NP5? If yes, any Caster should be a piece of cake. Early on in the game, you will fight Nitocris and several tough Sphinx (like literally tough, they are far more formidable than most "common" enemies from previous singularities. )
- Caster : You will encounter Hassans several times in Camelot. Any high level Caster should be enough
- Assasins : You will fight Ozymandias. Any high level Assasin should be enough. ST NP is recommended of course.
- Berserker : Against Lancelot, which is essentially a Ruler class, all Berserkers and Avengers are good enough. Equip your Berserker with Volumen Hydragryum to survive longer. Remember to bring one Arts-based hero to help increase your Berserker NP charge. Or use Heracles Bond CE. Additionally, other than lancelot,there will be one Ruler-class enemy in Camelot. Other than Ruler, Berserker will be very useful to Buster your way out of problem faster (or lose faster) against all class (except Tristan).

2. Mash is always useful in this game. No matter what kind of situation. Please max her to lv 60, and if you can 10/10/10 all her skills (should be easy) it will be better

3. Since you only have one good berserker, I recommend you to put him in your Sub lineup. Especially ST NP Berserker. Kaleidoscope is far more useful in this situation. If you put him in Starting lineup, Heracles Bond CE/Volumen is better. This is also my strategy. If I am against three type of enemies, then my starting lineup will be three types of heroes that are effective against them, while my Sub lineup include Mash and my ST Berserkers, plus one more hero with class advantage against Boss/more Berserker (i love Berserkers!!!). Remember, the boss class is given to you before you enter to battle. They are the top left in Enemy Class Tendency.

Last, there will be guaranteed paid gacha which will give you one guaranteed 5* servant. If you have $30, spend it now to get more firepower.

If my team can help you feel free to add me. My friend code is 015817920

NP 3 Orion was a big help to me. One shot all the sabers

First level altria mash hans and leondias to max. With a powerful frontline and reliable supports, you should be able to win.
Next you need some better servants in archers casters and assassins. For archer we get chloe and assassin scathach. You should look to pull in the upcoming summer banners.
For f2p options kid gil, medea, and henry jekyll are viable.
Most likely you will need more servants as you can no longer rely on friend supports to carry.

My support lineup is not too terrible. You can add me for support 544860208
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