I’m currently building up my +atk/-spd Katarina for the upcoming gauntlet. I have a 5* Tharja that I pulled awhile back and I don’t plan on using her. Would giving Katarina Rauorblade+ be a good idea?
I wouldn't do it. Blade tomes excel with a team, or at least one member built to buff them. With the VG coming up you wont necessarily have party members to give her buffs.
Unless someone in your friends list AND on your team sends out a devoted buff Ephraim/Eirika which would actually be really cool to do if you've got some people you know outside the game to talk to about it.
It depends a bit on what you plan to use her for? -SPD is not great but it could be salvaged into a OHKO style build.
Arena Offense - It's a bit more risky than it use to be but could still pay off. Visible buffs and blade tomes have been hit with a lot of nerfs recently. In particular, Katarina doesn't have the HP to handle Panic Ploy.
Arena Defense - It's a bad idea. The AI is too dumb to use blade tomes effectively.
Arena Assault - She should work here as a effective back-up Red.
Voting Gauntlet - Her default Owl would be better as you might not get visible buffs from allies.
Other PvE - It's a good idea.
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