Tiki is definitely worth investing in. Just ask red.
Someone rang? Oh, hey, Tiki. Yeah
Mythra
Tiki's a beast.
She's an astonishing physical tank, hits like a sledge, and her built-in Distant Counter breath is among the game's best. And, when you get her to 5*, her weapon becomes adaptive, hitting whichever's lower of Def and Res. Any hint of weakness in her foes becomes death.
So far she's been the undisputed top tier red dragon.
Biggest complaint against her is her mediocre Res. She can tank Falchion with a good build, but Naga shreds her, and if they even
field a Reinhardt you can actually hear her deflate.
Sounds like two balloons slowly letting out air.
Whenever you upgrade her to 4* check her IVs. Optimally you want +Atk or +Def to double down on her strengths, and -Spd since hers hardly matters. She'll also need a teammate who can tackle mages, especially blue mages.
In return you'll get something that a whole pile of normally terrifying physical threats will simply break themselves against.