Fujiwara no Mokou Guides

2 of the normal spells Lv 5, Possessed by Phoenix Lv 3, Reincarnation of Phoenix Lv 1
Pick 2 of the 3 normal spells you like and max them. Flying Phoenix can deal up to 1k damage, which is the highest fixed damage normal spell can deal in the game, but you need to use cyclone or elec stunner to hit it, and enemies can block it with AMS. Honest Man's Death deals very high damage(+@) and is instant cast spell, but enemies can simply use item or stat gamble to increase the non-main stats higher than main stat to avoid it. Phoenix's Tail deals the weakest damage among normal spells-OM*G I JUST CALLED 440 DAMAGE AS THE "WEAKEST"-, but it's AoE and easy to hit for beginners. Decision is up to you.
Possessed by Phoenix is what makes Mokou still imba at mid~late game. With this spell, you can take over the control of target for several seconds, meaning you can waste target's powerful moves on enemies. It even goes through AMS. How imba...
Reincarnation of Phoenix is not great, but decent AoE spell. The more closer you are with enemies, the more damage you deal. If you can manage to keep being close with enemies, it's certainly one of the strongest Last Word in lag-wisedamage-wise.