Unit Analysis by Team BethelFrankel
Class
Select-tile Converter that also generates Enhanced Tiles.
Overall
A
(SS at BT3)
Advantages
+With BT3: Preemptive Conversion is vital
+Web marks are a nice utility feature, even if they're more QoL than anything
+Very powerful chain extension thanks to how her tile placement works
+Nice synergy with Hiiro and MBT Hedy, as their cooldowns align.
Disadvantages
-Relatively inefficient total tile output for a unit that is a dedicated converter
-Competes with SEVERAL other great converters in forest that have higher overall output or other utility effects (Hiiro, Hedy, Gabriel, etc.)
-Equipment is... mostly a scam.
Explanation
Siobhan is one of the many "whale" converters that can feel incomplete and not as core as other options such as 4 tile converters when she is stuck at BT0. Thankfully, Siobhan only needs BT3 to push herself into SS tier. Note here that while select tile conversion is generally valued very highly amongst conversion types, Siobhan has stricter placement ranges compared to the likes of Hiiro or Bethlehem -- if you're not careful, you can create scenarios where you accidentally waste tiles.
Similarly, her cooldown lowering gimmick is generally useless, as getting the 15 tiles during Aurora Time to proc it is tricky at the best of times. While her Web Marks do help make up for her very low base HP and DEF, the shields they provide are minor (even at MBT!). That said, she does wonders in a dedicated Hiiro comp, and is only rivaled by Gabriel as an option in whale comps that want to hit consistent full circles on bosses. She's just a bit more strict and a little less individually impactful than many of her whale-friendly compatriots.