Rank up predictions are fun. First off, here are the ones that I think are possible. I’ve highlighted the ones that I think are most likely.

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All possible rank ups (in my opinion)

Day 2

3* Berserker - `Kiyohime NP`

or Lu Bu NP

5* Berserker - Kintoki S2/3 or Cu NP or `Raikou S3/NP`

Day 3

3* Archer - Robin S2/NP or Euryale S2 or `Kid Gil S2`

or Billy S1

4* Assassin - `Stheno S2`

or Scathach any or Wu S1 or Nito S2/NP or `Yu NP`

Note: Euryale/Stheno both getting the same/similar rank ups is possible.

Day 4

4* Lancer - `Lalter S3`

or `Vlad S2`

/NP or Jailter NP

5* Archer - `Gil S1`

or Arjuna S2 or `Moriarty NP`

Day 5

4* Caster - `Nursery S1`

/2 or Marie NP or `Gil`

S1/2/`NP`

or `Circe S2`

or Sheba S1/NP or `Miyu`

S1/`2`

5* Saber - Altria S1 or Okita NP or `Shiki S2`

or Musashi NP or `Arthur NP`

or Sigurd S1

Day 6

3* Lancer - `Proto Cu NP`

or Romulus NP or Diarmund S3 or Jaguar S2/NP

4* Berserker - `Herc NP`

or `Ibaraki S3`

/NP or Penth S1/NP or Nyalter NP

4* Archer - Atalante S2 or `Tristan S2`

or Helena NP or `Fujino`

S2/`NP`

5* Saber - Altria S1 or Okita NP or `Shiki S2`

or Musashi NP or `Arthur NP`

or Sigurd S1

As for actual predictions as to what they are, here goes.

Day 2

3* Berserker - Kiyohime

NP - Damage up, burn damage up (1000-1400), stun chance up (70-90%).

5* Berserker - Minamoto-no-Raikou

Skill 3 - 20-30% battery.

Day 3

3* Archer - Kid Gilgamesh

Skill 2 - reduce cooldown by 1, charm rate up (50-80%, guaranteed after NP), defence down 10-30%.

4* Assassin - Stheno

Skill 2 - reduce cooldown by 1 (maybe 2), defence down 40% (allows her to stack 60% def down, and 40% attack up).

Also possible that they give this to both Euryale and Stheno.

Day 4

4* Lancer - Altria Pendragon (Lancer Alter)

Skill 3 - 10-20% attack up, 10-20% self battery.

5* Archer - Moriarty

NP - Damage up, apply buff block.

Just for the memes because they seem to like giving Gil stuff, and he still has vanilla Charisma

5* Archer - Gilgamesh

Skill 1 - 15-25% attack up, gain 5-15 stars per turn.

Day 5

4* Caster - Nursery Rhyme

Skill 1 - Gain 5-15 stars, and gain 5-15 stars for 2 turns (basically, the turn she uses the skill, and the next 2 turns).

5* Saber - Ryougi Shiki (Saber)

Skill 2 - Buff removal resist 50-100% and evade 3 times, 3 turns.

Day 6

3* Lancer - Cu Chulainn (Prototype)

NP - Damage up, death chance 60-100%, defence down 30-50%.

4* Berserker - Heracles

NP - Damage up, heal 10,000 HP (level 80 with full 3* Fous he has 11,327 HP, so this is basically a full heal).

4* Archer - Tristan

Skill 2 - Remove demerit, 20-40% AoE quick for 1 turn (this gives you an actual reason to use him instead of David).

5* Saber - Arthur Pendragon (Prototype)

NP - Damage up, NP strength 40-80%

Shame that Gil was the Fate/Prototype archer, or day 6 would be the full Prototype cast. Unless I’m wrong about that. I haven’t actually read Prototype.