Walkthrough: Connected to Route 15 is Route 16, a small route with few Pokemon and Trainers. However, the Zygarde Lab where you can build your own Zygarde with the Cells you've been collecting.
Wild Pokemon:
Grasses - Daytime (Levels 30-33): Pelipper(50%), Gumshoos(30%), Slowpoke(20%)
Grasses - Nighttime (Levels 30-33): Pelipper(50%), Raticate(30%), Slowpoke(20%)
Berry Trees (Levels 30-33): Crabrawler(100%)
Zygarde Cells: There is one Zygarde Cell found here.
Trainers:
Scientist Reid - Level 32 Charjabug, Level 33 Muk
Items:
TM81 X-Scissor - Behind Zygarde Lab
PP Up - Far East
Pecha Berry - Berry Tree
Persim Berry - Berry Tree
Aspear Berry - Berry Tree
Oran Berry - Berry Tree
Sitrus Berry - Berry Tree
Lum Berry - Berry Tree
PokeMart (Throughout Game Progression):
Poke Ball - Great Ball - Ultra Ball - Potion - Super Potion - Hyper Potion - Max Potion - Full Restore - Revive - Antidote - Paralyze Heal - Awakening - Burn Heal - Ice Heal - Full Heal - Escape Rope - Repel - Super Repel - Max Repel - Honey - Adrenaline Orb