Wait, discard what I wrote, that may be actually true. Normal types immune to Normal in this game.
Well, you'll have to try something more complicated then. Instead of inflicting Stop with DDaiyousei, you could try a set like this:
- Miasma
- Spirit Barrier
- Barrier Option
- Move of choice
- Glamorous ability
EV's in Defense and HP really help with a set like this. Miasma, Spirit Barrier, and Barrier option are TM's no. 77, 63, and 64 and function like Toxic, Substitute, and Protect. Though 80/80 defenses aren't really great, you could try catching a Yuuka and using her to tank instead of Dai-chan, they're like level 45-50-ish in the wild, which might be good enough with a little bit of extra grinding to run a defensive set incorporating Mana of Grace (マナの恵み) which works like Synthesis (but at 10PP).
Another way of stalling would be DMedicine, also catchable at high level. She can run:
- Fountain of Youth
- Power Drain / Miasma
- Barrier Option
- Spirit Barrier
And stall endlessly by alternating Barrier Option and Spirit barrier after setting up (she will be able to heal continuous barriers for 16+ turns). Note that she can't switch out though. Another advantage of Medi-chan is her nice low cost of 80, allowing her to level quickly.
Yuuka's field also has the Prismrivers at high levels by the way, who have moves that are 4x effective against PReimu and will instagib her.
