Darius vs Pantheon Top Matchup
Darius Top wins 48.0% of 2,226 Low Elo games against Pantheon Top, -0.6 points vs expected, 2-patch window 26.19-26.20.
Researched on LoL patch 26.20. Tips are written to hold at any rank; stats come from Low Elo ranked games up to patch 26.20.
How to play as Darius
Respect Pantheon's short trades and spear poke before level 6; look for an extended fight at high health after he uses empowered Comet Spear(Q) or Aegis Assault(E).
If Pantheon is holding Aegis Assault(E), use Apprehend(E) straight into Noxian Guillotine(R) to reduce his time to turn and block the ultimate.
Aegis Assault(E) blocks damage from the front, so Pantheon can deny Noxian Guillotine(R) if he is facing Darius when it lands.
How to play as Pantheon
Use short trades and Comet Spear(Q) poke before level 6, but avoid taking an extended all-in against a healthy Darius after he reaches level 6.
Sources
These notes come from r/Dariusmains, checked against the champions' abilities.