Multiplayer

Vantage runs single-player out of the box. The same code runs networked with a small amount of wiring, and a sample for Netcode for GameObjects ships with the package. This page is honest about what is ready and what you still write.

Vantage does not depend on any networking framework. The sample uses Netcode for GameObjects; Mirror and FishNet fit the same seams.

The one rule

Every state change in the package first asks VtAuthority.IsLocal(component). In single-player the answer is always yes. Networked, the answer is “the server, or the owner of this unit”:

VtAuthority.IsLocalFn = c =>
{
    var netObject = c.GetComponentInParent<NetworkObject>();
    if (netObject == null) return true;
    return NetworkManager.Singleton.IsServer || netObject.IsOwner;
};

The server therefore runs everything. A client runs only its own unit: its cast bars, cooldowns and movement start locally, which is what keeps the game responsive. Objects without a network component stay local everywhere, so props and UI keep working.

How a cast travels

sequenceDiagram
    participant C as Client (owner)
    participant S as Server
    C->>C: TryCast: validate, charge, cast bar
    C->>S: ability id, target, point
    S->>S: TryCastNow: validate again, run effects
    S-->>C: pool values replicate back

A client-side IVtAbilityExecutor packs the resolved cast with VtAbilityRelay.Pack and sends it. The server resolves the id through the Definition Catalog and calls VtAbilityRelay.Apply, which runs TryCastNow: full validation without a second cast bar. Damage only ever happens on the server. The client’s copy of the monster refuses damage because it does not own it.

The co-op sample

Import Co-op (Netcode for GameObjects) from the package’s Samples tab after installing com.unity.netcode.gameobjects. It contains:

The sample’s README walks through the prefab setup. The short version: add NetworkObject, NetworkTransform, the sync and the executor to each unit prefab, swap the movement executor for VtClientAuthMovementExecutor, and create a Definition Catalog under Assets/Resources.

What to replicate yourself

The sample replicates position and pools. Everything else has an Apply...FromNet method on its component that updates state and fires the same events a local change would, so HUDs and combat text work on observers.

Resolve ids back to assets with the same Definition Catalog.

Dedicated server

Use the Dedicated Server build target with the same scene and the same sample components. The combat text presenter does not start in server builds. VtTickManager.Tick(dt) can drive the whole simulation from your own loop if you do not want Unity’s Update, see Ticking.

What is not solved

• Movement is client-authoritative. A modified client can teleport. Server-authoritative movement with prediction and reconciliation is yours to write behind IVtMovementExecutor.
• Resource costs are predicted. The client charges its own copy, the server charges again; the server’s values replicate back and win.
• Prediction of effects. Clients see a hit when the server’s pool value arrives, one round trip after the cast. Short cast times and snappy animations hide most of it.

Cheating

A host is trusted. A modified client can lie about its own position, never about damage, loot or quests. For public play, run a dedicated server and treat movement as the remaining gap.