diff --git a/src/components/md-yarn-spinner.tsx b/src/components/md-yarn-spinner.tsx
index 001e3b0..bba73a7 100644
--- a/src/components/md-yarn-spinner.tsx
+++ b/src/components/md-yarn-spinner.tsx
@@ -2,9 +2,8 @@ import { customElement, noShadowDOM } from 'solid-element';
 import { For, Show, createEffect } from 'solid-js';
 import type {TextResult, RuntimeResult, OptionsResult} from '../yarn-spinner/runtime/results';
 import { createYarnStore } from './stores/yarnStore';
-import {RunnerOptions} from "../yarn-spinner/runtime/runner";
 
-customElement<RunnerOptions>('md-yarn-spinner', {startAt: 'start'}, (props, { element }) => {
+customElement<{start: string}>('md-yarn-spinner', {start: 'start'}, (props, { element }) => {
   noShadowDOM();
   
   let historyContainer: HTMLDivElement | undefined;
diff --git a/src/components/stores/ttrpgRunner.ts b/src/components/stores/ttrpgRunner.ts
index dc4a523..d59b1ab 100644
--- a/src/components/stores/ttrpgRunner.ts
+++ b/src/components/stores/ttrpgRunner.ts
@@ -38,7 +38,7 @@ export function getTtrpgFunctions(runner: IRunner){
     }
     /* stat related */
     function ensure_stat(stat: string){
-        if(!runner.getVariable(stat)){
+        if(runner.getVariable(stat) === undefined){
             const statBase = `${stat}_base`;
             const statMod = `${stat}_mod`;
             const statDamage = `${stat}_damage`;
@@ -74,6 +74,7 @@ export function getTtrpgFunctions(runner: IRunner){
         const progress = runner.getVariable(key) as number || 0;
         const newProgress = progress + Math.ceil(Math.random() * 4);
         runner.setVariable(key, newProgress);
+        console.log(`check ${stat}(${statVal}) ${pass ? 'pass' : 'fail'}, now ${newProgress}`);
         return pass ? newProgress : -newProgress;
     }
     function rollStat(){
@@ -94,15 +95,17 @@ export function getTtrpgFunctions(runner: IRunner){
         heal(stat, 1);
     }
     return {
-        add_minutes: add_minute,
-        add_hours: add_hour,
-        add_days: add_day,
-
-        damage,
-        heal,
-        check,
-
-        fatigue,
-        regen,
-    };
+        commands: {
+            add_minute,
+            add_hour,
+            add_day,
+            damage,
+            heal,
+            fatigue,
+            regen
+        } as Record<string, (...args: any[]) =>any>,
+        functions: {
+            check
+        } as Record<string, (...args: any[]) =>any>
+    }
 }
\ No newline at end of file
diff --git a/src/components/stores/yarnStore.ts b/src/components/stores/yarnStore.ts
index 5e27acb..4c0c2fd 100644
--- a/src/components/stores/yarnStore.ts
+++ b/src/components/stores/yarnStore.ts
@@ -4,6 +4,7 @@ import {compile, parseYarn, YarnRunner} from "../../yarn-spinner";
 import {loadElementSrc, resolvePath} from "../utils/path";
 import {createStore} from "solid-js/store";
 import {RunnerOptions} from "../../yarn-spinner/runtime/runner";
+import {getTtrpgFunctions} from "./ttrpgRunner";
 
 type YarnSpinnerStore = {
     dialogueHistory: (RuntimeResult | OptionsResult['options'][0])[],
@@ -12,7 +13,7 @@ type YarnSpinnerStore = {
     runnerInstance: YarnRunner | null,
 }
 
-export function createYarnStore(element: HTMLElement, props: RunnerOptions){
+export function createYarnStore(element: HTMLElement, props: {start: string}){
     const [store, setStore] = createStore<YarnSpinnerStore>({
         dialogueHistory: [],
         currentOptions: null,
@@ -39,19 +40,11 @@ export function createYarnStore(element: HTMLElement, props: RunnerOptions){
             const program = compile(ast);
 
             const runner = new YarnRunner(program, {
-                functions: {
-                    check(id: string, stat: string): number {
-                        const statVal = runner.getVariable(stat) as number || 10;
-                        const pass = Math.ceil(Math.random() * 20) <= statVal;
-                        const key = `${id}_${pass ? 'pass' : 'fail'}`;
-                        const progress = runner.getVariable(key) as number || 0;
-                        const newProgress = progress + Math.ceil(Math.random() * 4);
-                        runner.setVariable(key, newProgress);
-                        return pass ? newProgress : -newProgress;
-                    }
-                },
-                startAt: props.startAt,
+                startAt: props.start,
             });
+            const {commands, functions} = getTtrpgFunctions(runner);
+            runner.registerFunctions(functions);
+            runner.registerCommands(commands);
             return runner;
         } catch (error) {
             console.error('Failed to initialize YarnRunner:', error);
diff --git a/src/yarn-spinner/runtime/evaluator.ts b/src/yarn-spinner/runtime/evaluator.ts
index 1e48b66..7c65128 100644
--- a/src/yarn-spinner/runtime/evaluator.ts
+++ b/src/yarn-spinner/runtime/evaluator.ts
@@ -499,4 +499,11 @@ export class ExpressionEvaluator {
     getVariable(name: string): unknown {
         return this.variables[name];
     }
+    
+    registerFunctions(functions: Record<string, (...args: unknown[]) => unknown>){
+        this.functions = {
+            ...this.functions,
+            ...functions
+        }
+    }
 }
diff --git a/src/yarn-spinner/runtime/runner.ts b/src/yarn-spinner/runtime/runner.ts
index 627731c..b54f8fb 100644
--- a/src/yarn-spinner/runtime/runner.ts
+++ b/src/yarn-spinner/runtime/runner.ts
@@ -28,7 +28,6 @@ type CompiledOption = {
 export class YarnRunner {
     private readonly program: IRProgram;
     private readonly variables: Record<string, unknown>;
-    private readonly functions: Record<string, (...args: unknown[]) => unknown>;
     private readonly handleCommand?: (command: string, parsed?: ReturnType<typeof parseCommand>) => void;
     private readonly commandHandler: CommandHandler;
     private readonly evaluator: ExpressionEvaluator;
@@ -59,7 +58,7 @@ export class YarnRunner {
                 this.variables[normalizedKey] = value;
             }
         }
-        this.functions = {
+        let functions = {
             // Default conversion helpers
             string: (v: unknown) => String(v ?? ""),
             number: (v: unknown) => Number(v),
@@ -115,12 +114,25 @@ export class YarnRunner {
         } as Record<string, (...args: unknown[]) => unknown>;
         this.handleCommand = opts.handleCommand;
         this.onStoryEnd = opts.onStoryEnd;
-        this.evaluator = new ExpressionEvaluator(this.variables, this.functions, this.program.enums);
+        this.evaluator = new ExpressionEvaluator(this.variables, functions, this.program.enums);
         this.commandHandler = opts.commandHandler ?? new CommandHandler(this.variables);
         this.nodeTitle = opts.startAt;
 
         this.step();
     }
+    
+    public registerFunctions(functions: Record<string, (...args: unknown[]) => unknown>){
+        this.evaluator.registerFunctions(functions);
+    }
+    
+    public registerCommands(commands: Record<string,  (args: unknown[], evaluator?: ExpressionEvaluator) => void | Promise<void>>) {
+        for(const key in commands){
+            this.commandHandler.register(key, (args, evaluator) => {
+                if(!evaluator) return;
+                commands[key].call(this, args.map(arg => evaluator.evaluateExpression(arg)));
+            });
+        }
+    };
 
     /**
      * Resolve a node title to an actual node (handling node groups).
@@ -599,6 +611,8 @@ export class YarnRunner {
      * Get variable value.
      */
     getVariable(name: string): unknown {
+        if(this.evaluator.isSmartVariable(name))
+            return this.evaluator.evaluateExpression(`$${name}`);
         return this.variables[name];
     }