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Here, you probably should go to the Pharmacy and then explore, first go to the person in the house above the Pharmacy, he will give you a Shuckle it is probably best to give this to day-care along with a Ditto so head there after you go to the Lighthouse. Next go to the Pokémon Center and prepare for a battle, now go north to see Suicune, after that Eusine appears and wants a battle. When you win go to the Lighthouse

[edit] Trainers

• Mysticalman Eusine:
  • Drowzee (lvl. 23, 500 EXP)
  • Haunter (lvl. 23, 621 EXP)
  • Electrode (lvl. 25, 802 EXP) and 2500

[edit] Items