Welcome! Come one, come all! 
It’s time for Mister Mystery’s Buster Special, but be warned, he only comes around on Sundays for whatever reason, what, was DW too scared of having Merlin available every day of the event? 
First up, we have the star of the banner and one of the Big Four Support Casters, the limited 5* Merlin!
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He’s a funny and powerful court wizard who guides Artoria on her journey, gets his spells tongue-twisted and also pretends to be a beautiful internet idol with his Tower of Avalon’s top-tier Wi-Fi to be fair, it’s only competing with Chaldea’s Wi-Fi since all of humanity’s Wi-Fi is down in the FGOverse. He also has the world record for being the world’s oldest shut-in! There are lots of other things I like about him but I’ll try to keep it short for now. 
Gameplay rundown
Gameplaywise, he’s the (current) best Buster support in the game. His first skill is Dreamlike Charisma, which buffs the party’s Atk stat and boosts their NP gauge by 20%. Illusion, his second skill, grants teamwide invincibility and decreases the enemy team’s crit rate, very useful for protecting against an AoE NP. His NP grants the team healing and NP gauge up per turn, and also grants crit stars per turn.
Merlin’s big skill here is his S3 Hero Creation, which boosts Buster for one ally for three turns as well as their max HP, and for one turn, increases their crit strength. One push of this button and your chosen Servant’s Busters and crits will hit like trucks
He is geared towards Buster crit playstyles and stalling and does very well at both of those things. He isn’t as good for 3T farming (if you’re interested in 3T Buster farming, look no further than Koyanskaya of Light next anni), but if you like facecarding and unga bunga-ing your farming, take him along.
If you do not currently have Merlin and choose not to roll for him here (which I’m certain a huge chunk of you are because of a particular female Caster looming closely in the distance 
), your next bets to get him are GSSRs, or a White Day banner coming up in 2024. Merlin will also get a simple costume with glasses during that time 
Up next is the 4* rateup Servant of the banner, the permanent Saber Siegfried!
(Official game art. Artist: Ototsugu Konoe)
The cool and calm slayer of Fáfnir and wielder of Balmung is back with a stylish new tight suit. Or an RP if you claimed the costume last year. This look does a good job at showing off his glowing scar and also gives him a sharp pair of glasses. He tries his best to crack an intellectual joke from time to time while wearing this outfit. 
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Gameplay rundown
As Siegfried’s claim to fame is his slaying of the evil dragon Fáfnir, his kit reflects this and it’s what he does best.
His S3 gives him Special Attack and Defense against [Dragon] enemies, and it also grants him a one-turn Buster buff. His NP, Balmung, is Buster AoE and deals Special Attack damage to [Dragon] enemies. With its buff, it also increases his NP gain for 3 turns.
His other two skills are Golden Rule and Disengage; the former increases his NP gain, and the latter restores his HP a little and also clears all his debuffs. As a Cú main, I find Disengage to be pretty useful for its debuff wiping.
Since his main strength is Busters against dragons, why not team Merlin with him, who you can get off this banner?
Siegfried has a few future rateups: one on the next Saber class banner and one on the Apocrypha banner that came to JP in October 2021 (please note it could come earlier to us in NA). He is a permanent pool Servant, so he can also spook you at any time.
And finally, the 3* rate-up servant and our Quick special guest on the Buster Special, the permanent Assassin Fuuma “Evil-wind” Kotarou!
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The young leader of the Fuuma clan drops his stylish scarf for an equally-as-cool cap and sleeveless hoodie in this event, where he helps Master and co. gather intel on the Swimsuit Swordmasters. He specializes in stealth, and in his NP, a healthy dose of shadowclone jutsu as he inflicts confusion on the enemy team.
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Gameplay rundown
Kotarou’s buffed S3 inflicts Nullify Buff on all enemies, which is very rare among 3* Servants. It also decreases Def and Debuff Resist for all enemies, but the main draw of this skill is the Nullify Buff.
His other skills are Sabotage and Ninjutsu; Sabotage being an Atk and Crit Rate debuff on all enemies, while Ninjutsu (which has a rating of A+++ I might add), grants a chosen ally a 1-turn Evade and an increased C. Star Drop Rate.
His NP, Immortal Chaos Brigade, is Quick AoE, and inflicts Confusion and a Def debuff on those enemies. (Confusion is a chance of Skill Seal each turn, for those who don’t know or forgot).
Overall, Kotarou’s pretty great at debuffing enemies, and he can inflict Nullify Buff which is pretty strong on a 3* Servant.
I don’t think that Kotarou has any future rateups (for those who have him as a super-favorite and want to get his coins reliably), but he is a permanent, non-story locked 3*, so he should come up naturally as you roll SQ. He is also in the FP pool.
Banner Schedule
As the name of the banner suggests, it is only available to summon on on Sundays. Do note that this means Sundays in Pacific Time, so you won’t be able to roll until it’s Sunday in that timezone.
If the image isn’t loading for you, there are 3 Sundays the banner is available, and they are:
- May 29
- June 5
- June 12
If you’re one of the few who has big plans to roll on this banner, or if you can only spare a few yolos thanks to a certain other support Caster coming up in July, may the funny Buster wizard have mercy on your SQs and answer your summons try offering candy apples, I hear he likes that they turn your tongue red Good luck!!
Before I finish, some more lovely art of these three to end this off:
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a small note, I set most of the pieces of art in this thread to 75% size to reduce scrolling time. If you wish to save these pieces of fanart, click on the image to view it full size and then save it, or save it from its source.
) but I finally managed to drag him home on the new years gssr. Good luck to everyone who still needs the OG Buster support 
& 95 
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