Nocturne vs Bel'Veth Jungle Matchup

Why Bel'Veth is favored

Bel'Veth permanently gains attack speed from large-monster takedowns, and a Nocturne matchup guide recommends invading her throughout the game to deny those Death in Lavender stacks and pressing before she scales. If Nocturne cannot limit her camp takedowns, that farm-driven scaling gives Bel'Veth a way to build her edge.

How to play as Nocturne

Save Shroud of Darkness(W) for Bel'Veth's Above and Below(W) knock-up; players identify it as the key spell to block, and a successful block also gives you attack speed.

Invade Bel'Veth's camps when the map allows and pressure her before she stacks freely; her permanent Death in Lavender attack-speed stacks come from large-monster takedowns.

Above and Below(W) knocks up its targets, and Shroud of Darkness(W) can block one ability and grant Nocturne attack speed when the block succeeds.

How to play as Bel'Veth

Avoid a direct early 1v1 if you do not have an advantage; track Nocturne and counter-gank his Paranoia(R) plays instead of meeting his preferred fight alone.

Sources

These notes come from r/BelVethMains and mobafire.com, checked against the champions' abilities.