Scolipede
- STAB super effective against Opal, Bede, Piers, Marnie, and several Pokemon in the Champion Cup
- Very fast, with respectable Attack
- Two decent Abilities, and one excellent one (Speed Boost)
- Learns moves like Megahorn, Poison Jab, Earthquake, Baton Pass, Throat Chop, and Swords Dance
- Evolves earlier than Krookodile
- Quite frail
- Venipede and Whirlipede aren't exactly great
Krookodile
- STAB super effective against Gordie, part of Raihan's team, and plenty of Pokemon in the Champion Cup
- Better Attack than Scolipede
- Two incredible non-HA Abilities
- Learns moves like Earthquake, Outrage, Close Combat, Darkest Lariat, and Stone Edge
- Decent Speed
- Slightly stronger defensively than Scolipede
- Obtainable later than Scolipede
- Tons of weaknesses
Based on your team's needs, I'd say Scolipede. It can do super effective damage to Opal, and it's very strong throughout the rest of the game as well. Krookodile is by no means bad, but Scolipede works better for your team.
Scolipede @ Black Sludge / Life Orb / anything
Ability: Speed Boost / Swarm
- Poison Jab
- Megahorn / X-Scissor
- Throat Chop
- Earthquake
Hope I helped!
