diff --git a/index.html b/index.html
index 83f2606..bc37236 100644
--- a/index.html
+++ b/index.html
@@ -509,7 +509,8 @@ <h2><a name="changelog">Changelog</a></h2>
       <h3><time>July 19, 2024</time></h3>
       <ul>
         <li>Added new seed naming scheme.</li>
-        <li>Performance enhancement: Moved preset sorting to browser JS file.</li>
+        <li>Performance enhancement: Presets now load on demand instead of being loaded every randomization iteration.</li>
+        <li>Performance enhancement: Added debug mode foundation to Command Line.</li>
       </ul>
       <h3><time>July 16, 2024</time></h3>
       <ul>
diff --git a/randomize b/randomize
index 23d9d15..bc80b48 100755
--- a/randomize
+++ b/randomize
@@ -8,6 +8,7 @@ const Worker = require('worker_threads').Worker
 const constants = require('./src/constants')
 const errors = require('./src/errors')
 const extension = require('./src/extension')
+const presets = require('./build/presets')
 const randomizeStats = require('./src/randomize_stats')
 const randomizeRelics = require('./src/randomize_relics')
 const randomizeItems = require('./src/randomize_items')
@@ -406,6 +407,39 @@ const tournamentHelp = [
   '- The clock room statue is always open.',
 ].join('\n')
 
+const presetHelp = [
+  'Presets specify collection of randomization options. A preset is enabled',
+  'by using argument syntax.',
+  '',
+  'Preset format:',
+  '  p:<preset>',
+  '',
+  'This randomizer has several built-in presets:',
+].concat(presets.filter(function(preset) {
+  return !preset.hidden
+}).map(function(preset) {
+  return '  ' + preset.id + (preset.id === 'safe' ? ' (default)' : '')
+})).concat([
+  '',
+  'Use `--help <preset>` for information on a specific preset.',
+  '',
+  'Examples:',
+  '  p:safe        Use Safe preset',
+  '  p:empty-hand  Use Empty Hand preset',
+  '',
+  'When using the `$0` utility, you can use the `--preset` shorthand to',
+  'specify a preset:',
+  '  $0 -p speedrun  # Use speedrun preset',
+  '',
+  'Preset options may be overridden by specifying an options string:',
+  '  $0 -p adventure --opt d:*:Peanuts-  # Adventure with only Peanut drops',
+  '',
+  'A special negation syntax can be used in the options string to disable',
+  'randomizations that a preset would otherwise enable. To negate a',
+  'randomization, precede its letter with a tilde ("~"):',
+  '  $0 -p adventure --opt ~m  # Adventure but without music randomization',
+]).join('\n')
+
 function presetMetaHelp(preset) {
   const options = preset.options()
   let locations = relics.filter(function(relic) {
@@ -602,6 +636,11 @@ const yargs = require('yargs')
     describe: 'Quickens warp animation when using teleporters.',
     type: 'boolean',
   })
+  .option('debug', {
+    alias: 'D',
+    describe: 'Debug mode.',
+    type: 'boolean',
+  })
   .option('disable-accessibility-patches', {
     alias: 'a',
     describe: 'Disable accessibility patches',
@@ -649,45 +688,22 @@ if (process.argv.length < 3) {
   console.error('\nAt least 1 argument or option required')
   process.exit(1)
 }
+// check for debug
+if ('debug' in argv) {
+  if ('tournament' in argv) {
+    console.error('\nYou cannot run debug mode at the same time as tournament mode.')
+    process.exit(1)
+  } else {
+    console.log('Begin Debug output:')
+  }
+}
+if ('debug' in argv) {console.log('randomize | Checking for help flags')}
 // Check for help.
 if ('help' in argv) {
   if (!argv.help) {
     yargs.showHelp()
     process.exit()
   }
-  const presets = require('./build/presets')
-  const presetHelp = [
-    'Presets specify collection of randomization options. A preset is enabled',
-    'by using argument syntax.',
-    '',
-    'Preset format:',
-    '  p:<preset>',
-    '',
-    'This randomizer has several built-in presets:',
-  ].concat(presets.filter(function(preset) {
-    return !preset.hidden
-  }).map(function(preset) {
-    return '  ' + preset.id + (preset.id === 'safe' ? ' (default)' : '')
-  })).concat([
-    '',
-    'Use `--help <preset>` for information on a specific preset.',
-    '',
-    'Examples:',
-    '  p:safe        Use Safe preset',
-    '  p:empty-hand  Use Empty Hand preset',
-    '',
-    'When using the `$0` utility, you can use the `--preset` shorthand to',
-    'specify a preset:',
-    '  $0 -p speedrun  # Use speedrun preset',
-    '',
-    'Preset options may be overridden by specifying an options string:',
-    '  $0 -p adventure --opt d:*:Peanuts-  # Adventure with only Peanut drops',
-    '',
-    'A special negation syntax can be used in the options string to disable',
-    'randomizations that a preset would otherwise enable. To negate a',
-    'randomization, precede its letter with a tilde ("~"):',
-    '  $0 -p adventure --opt ~m  # Adventure but without music randomization',
-  ]).join('\n')
   const topics = {
     options: optionsHelp,
     drops: dropsHelp,
@@ -720,6 +736,7 @@ if ('help' in argv) {
 if (argv.compat) {
   version = argv.compat
 }
+if ('debug' in argv) {console.log('randomize | Checking for seed string')}
 // Check for seed string.
 if ('seed' in argv) {
   if ('noSeed' in argv) {
@@ -729,6 +746,7 @@ if ('seed' in argv) {
   }
   seed = argv.seed.toString()
 }
+if ('debug' in argv) {console.log('randomize | Checking for base URL')}
 // Check for base url.
 if (argv.url) {
   baseUrl = argv.url
@@ -737,6 +755,7 @@ if (argv.url) {
 if (argv.noSeed) {
   argv.url = ''
 }
+if ('debug' in argv) {console.log('randomize | Checking for expected checksum')}
 // Check for expected checksum.
 if ('expectChecksum' in argv) {
   if (!('seed' in argv) && !argv._[0]) {
@@ -752,6 +771,7 @@ if ('expectChecksum' in argv) {
   expectChecksum = parseInt(argv.expectChecksum, 16)
   haveChecksum = true
 }
+if ('debug' in argv) {console.log('randomize | Checking for randomization string from CLI')}
 // Check for randomization string.
 if ('options' in argv) {
   try {
@@ -762,6 +782,7 @@ if ('options' in argv) {
     process.exit(1)
   }
 }
+if ('debug' in argv) {console.log('randomize | Checking for preset name')}
 // Check for preset.
 if ('preset' in argv) {
   try {
@@ -773,8 +794,6 @@ if ('preset' in argv) {
       options || {},
       util.optionsFromString('p:' + argv.preset)
     )
-    // This env variable is then used in index.js to determine which preset files to load from.
-    process.env.chosenPreset = argv.preset  
   } catch (e) {
     yargs.showHelp()
     console.error('\n' + e.message)
@@ -818,6 +837,7 @@ if (options && 'preset' in options
     process.exit(1)
   }
 }
+if ('debug' in argv) {console.log('randomize | Assume safe if no preset')}
 // Assume safe if negations are specified without a preset.
 if (options) {
   const copy = Object.assign({}, options)
@@ -830,7 +850,7 @@ if (options) {
     options.preset = 'safe'
   }
 }
-
+if ('debug' in argv) {console.log('randomize | Checking for URL seed')}
 // Check for seed url.
 if (argv._[0]) {
   if ('noSeed' in argv) {
@@ -869,6 +889,7 @@ if (argv._[0]) {
     console.error('\nArgument seed is not url seed')
     process.exit(1)
   }
+  if ('debug' in argv) {console.log('randomize | Checking for options matching arguments')}
   // Ensure randomizations match if given using --options.
   const optionStr = util.optionsToString(options)
   if (('options' in argv && argv.options !== optionStr)
@@ -877,6 +898,7 @@ if (argv._[0]) {
     console.error('\nArgument randomizations are not url randomizations')
     process.exit(1)
   }
+  if ('debug' in argv) {console.log('randomize | Checking for expected checksum matching checksum')}
   // Ensure checksum match if given using --expect-checksum.
   if ('expectChecksum' in argv && url.checksum != expectChecksum) {
     yargs.showHelp()
@@ -884,6 +906,7 @@ if (argv._[0]) {
     process.exit(1)
   }
 }
+if ('debug' in argv) {console.log('randomize | Enable race options')}
 // Set options for --race.
 if (argv.race) {
   argv.url = ''
@@ -891,10 +914,12 @@ if (argv.race) {
     argv.verbose = 2
   }
 }
+if ('debug' in argv) {console.log('randomize | Enable quiet option')}
 // Suppress output if quiet argument specified.
 if (argv.quiet) {
   argv.verbose = 0
 }
+if ('debug' in argv) {console.log('randomize | Enable option defaults if non specified')}
 // Create default options if none provided.
 if (typeof(seed) === 'undefined' && !argv.noSeed) {
   seed = (new Date()).getTime().toString()
@@ -902,6 +927,7 @@ if (typeof(seed) === 'undefined' && !argv.noSeed) {
 if (!options) {
   options = util.optionsFromString(constants.defaultOptions)
 }
+if ('debug' in argv) {console.log('randomize | Set complexity')}
 // Check for complexity setting.
 if ('complexity' in argv) {
   let applied = Object.assign({}, options)
@@ -923,6 +949,7 @@ if ('complexity' in argv) {
       process.exit(1)
     }
   }
+  if ('debug' in argv) {console.log('randomize | Set seed goals')}
   // Get seed goals.
   let complexity = Object.getOwnPropertyNames(applied.relicLocations).filter(
     function(key) {
@@ -943,26 +970,32 @@ if ('complexity' in argv) {
     process.exit(1)
   }
 }
+if ('debug' in argv) {console.log('randomize | Set tournament mode')}
 // Enable tournament mode if specified.
 if (argv.tournament) {
   options.tournamentMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set color rando')}
 // Enable color rando mode if specified. - MottZilla
 if (argv.colorrando) { // Enable Color Randomizations
   options.colorrandoMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set magic max')}
 // Enable magic max mode if specified. - MottZilla
 if (argv.magicmax) { // Adds MP Vessel to replace Heart Vessel - eldrich
   options.magicmaxMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set anti-freeze')}
 // Enable anti-freeze mode if specified. - eldri7ch
 if (argv.antifreeze) { // Removes screen freezes from level-up and acquisitions - eldrich
   options.antiFreezeMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set my purse')}
 // Enable my purse mode if specified. - eldri7ch
 if (argv.mypurse) { // Adds MP Vessel to replace Heart Vessel - eldrich
   options.mypurseMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set map colors')}
 // Map Color Features if specified. - eldri7ch
 if ('mapcolor' in argv && typeof(argv.mapcolor) !== 'undefined') {
   let termsAllowed = 'u,r,b,g,y,p,k'
@@ -974,29 +1007,40 @@ if ('mapcolor' in argv && typeof(argv.mapcolor) !== 'undefined') {
     options.mapcolorTheme = argv.mapcolor.toString()
   }
 }
+if ('debug' in argv) {console.log('randomize | Set infinite wing smash')}
 // Enable infinite wing smash mode if specified. - eldri7ch
 if (argv.iws) { // Makes wing smashes essentially infinite - eldrich
   options.iwsMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set fast warp')}
 // Enable fast warp mode if specified. - eldri7ch
 if (argv.fastwarp) { // quickens teleporter warp animation - eldrich
   options.fastwarpMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set no prologue')}
 // Enable no prologue mode if specified. - eldri7ch
 if (argv.noprologue) { // Removes prologue - eldrich
   options.noprologueMode = true
 }
+if ('debug' in argv) {console.log('randomize | Set debug')}
+// Enable debug mode if specified. - eldri7ch
+if (argv.debug) { // Enables debug - eldrich
+  options.debugMode = true
+}
+if ('debug' in argv) {console.log('randomize | Set verbosity')}
 // Set misc options.
 if ('verbose' in argv) {
   options.verbose = argv.verbose
 }
 const info = util.newInfo()
+if ('debug' in argv) {console.log('randomize | Set seed if not pre-defined')}
 // Add seed to log info if not provided through command line.
 if (!argv.noSeed && (!('url' in argv) || argv._[0])) {
   info[1]['Seed'] = seed
 }
 let fd
 let size
+if ('debug' in argv) {console.log('randomize | Read BIN file')}
 // Read bin file if provided.
 if ('inBin' in argv) {
   eccEdcCalc = require('./src/ecc-edc-recalc-js')
@@ -1017,7 +1061,7 @@ if ('inBin' in argv) {
     process.exit(1)
   }
 }
-
+if ('debug' in argv) {console.log('randomize | Start randomization')}
 (async function randomize() {
   try {
     let check
@@ -1025,12 +1069,13 @@ if ('inBin' in argv) {
     let startTime
     let endTime
 
-    startTime = performance.now()    
-    const presets = require('./build/presets') 
+    startTime = performance.now()
+
     if (!argv.noSeed) {
       check = new util.checked(typeof(fd) === 'object' ? undefined : fd)
       let applied
       try {
+        if ('debug' in argv) {console.log('randomize | function: randomize | Check for overriding preset')}
         // Check for overriding preset.
         let override
         for (let preset of presets) {
@@ -1040,6 +1085,7 @@ if ('inBin' in argv) {
             break
           }
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Retrieve user-specified options')}
         // Get user specified options.
         if (!override) {
           applied = util.Preset.options(options)
@@ -1052,6 +1098,7 @@ if ('inBin' in argv) {
       try {
         let rng
         let result
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize stats')}
         // Randomize stats.
         rng = new require('seedrandom')(util.saltSeed(
           version,
@@ -1062,12 +1109,14 @@ if ('inBin' in argv) {
         result = randomizeStats(rng, applied)
         const newNames = result.newNames
         check.apply(result.data)
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize Relics:assemble workers')}
         // Randomize relics.
         const cores = os.cpus().length
         const workers = Array(util.workerCountFromCores(cores))
         for (let i = 0; i < workers.length; i++) {
           workers[i] = new Worker('./src/worker.js')
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize Relics:call util function')}
         result = await util.randomizeRelics(
           version,
           applied,
@@ -1078,8 +1127,9 @@ if ('inBin' in argv) {
           4,
         )
         util.mergeInfo(info, result.info)
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize Relics:Write new relic map')}
         // Write relics mapping.
-        rng = new require('seedrandom')(util.saltSeed(
+        rng = new require('seedrandom')(util.saltSeed( //new rng generation?
           version,
           options,
           seed,
@@ -1092,6 +1142,7 @@ if ('inBin' in argv) {
           newNames,
         )
         check.apply(result.data)
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize Items:call util function')}
         // Randomize items.
         result = await util.randomizeItems(
           version,
@@ -1103,8 +1154,10 @@ if ('inBin' in argv) {
           result.items,
           newNames,
         )
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize Items:Write new item map')}
         check.apply(result.data)
         util.mergeInfo(info, result.info)
+        if ('debug' in argv) {console.log('randomize | function: randomize | Randomize Music')}
         // Randomize music.
         rng = new require('seedrandom')(util.saltSeed(
           version,
@@ -1113,42 +1166,53 @@ if ('inBin' in argv) {
           3,
         ))
         check.apply(randomizeMusic(rng, applied))
+        if ('debug' in argv) {console.log('randomize | function: randomize | Apply patches from options')}
+        if ('debug' in argv) {console.log('randomize | function: randomize | Tournament Mode')}
         if (options.tournamentMode) {
           // Apply tournament mode patches.
           check.apply(util.applyTournamentModePatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Magicmax Mode')}
         if (options.magicmaxMode || applied.magicmaxMode) { // Adds MP Vessel to replace Heart Vessel - eldrich
           // Apply magic max mode patches. - MottZilla
           check.apply(util.applyMagicMaxPatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Anti-Freeze Mode')}
         if (options.antiFreezeMode || applied.antiFreezeMode) { // Removes screen freezes on relic / vessel collection and level-up - eldrich
           // Apply anti-freeze mode patches. - eldri7ch
           check.apply(util.applyAntiFreezePatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | That\'s my purse! Mode')}
         if (options.mypurseMode || applied.mypurseMode) { // Removes Death from Entrance - eldrich
           // Apply Death repellant patches. - eldri7ch
           check.apply(util.applyMyPursePatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Map colors')}
         if ('mapcolor' in argv) { // Colors the map - eldrich
           // Apply map color patches. - eldri7ch
           let mapcol = argv.mapcolor
           check.apply(util.applyMapColor(mapcol))
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Infinite Wing Smash Mode')}
         if (options.iwsMode || applied.iwsMode) { // Makes wing smash essentially infinite - eldrich
           // Apply infinite wing smashe mode patches. - eldri7ch
           check.apply(util.applyiwsPatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Fast Warps Mode')}
         if (options.fastwarpMode || applied.fastwarpMode) { // Quickens teleporter warp animations - eldrich
           // Apply fast warp mode patches. - eldri7ch
           check.apply(util.applyfastwarpPatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | No Prologue Mode')}
         if (options.noprologueMode || applied.noprologueMode) { // removes prologue - eldrich
           // Apply no prologue mode patches. - eldri7ch
           check.apply(util.applynoprologuePatches())
         }
+        if ('debug' in argv) {console.log('randomize | function: randomize | Apply Writes')}
         // Apply writes.
         check.apply(util.applyWrites(rng, applied))
       } catch (err) {
+        if ('debug' in argv) {console.log('randomize | function: randomize | Error catching')}
         console.error('Seed: ' + seed)
         if (errors.isError(err)) {
           console.error('Error: ' + err.message)
@@ -1157,6 +1221,7 @@ if ('inBin' in argv) {
         }
         process.exit(1)
       }
+      if ('debug' in argv) {console.log('randomize | function: randomize | Set seed text in menu')}
       util.setSeedText(
         check,
         seed,
@@ -1165,16 +1230,19 @@ if ('inBin' in argv) {
         options.tournamentMode,
       )
       checksum = await check.sum()
+      if ('debug' in argv) {console.log('randomize | function: randomize | Checksum verification')}
       // Verify expected checksum matches actual checksum.
       if (haveChecksum && expectChecksum !== checksum) {
         console.error('Checksum mismatch.')
         process.exit(1)
       }
     }
+    if ('debug' in argv) {console.log('randomize | function: randomize | Accessibility patches')}
     if (!argv.disableAccessibilityPatches) {
       // Apply accessibility patches.
       check.apply(applyAccessibilityPatches())
     }
+    if ('debug' in argv) {console.log('randomize | function: randomize | Show url if not provided as arg')}
     // Show url if not provided as arg.
     if ('url' in argv && !argv._[0] && !argv.quiet) {
       console.log(util.optionsToUrl(
@@ -1185,12 +1253,16 @@ if ('inBin' in argv) {
         baseUrl,
       ))
     }
+    if ('debug' in argv) {console.log('randomize | function: randomize | Show spoilers')}
     // Print spoilers.
     if (argv.verbose > 0) {
       let verbose = argv.verbose
       if (options.tournamentMode && argv.verbose >= 2) {
         verbose = 2
       }
+      if ('debug' in argv && argv.verbose <= 4) {
+        verbose = 4
+      }
       const text = util.formatInfo(info, verbose)
 
       //start calculating the time elapsed
@@ -1211,6 +1283,8 @@ if ('inBin' in argv) {
     }
     if (!argv.noSeed) {
       if ('out' in argv) {
+        if ('debug' in argv) {console.log('Continue debug output:')}
+        if ('debug' in argv) {console.log('randomize | function: randomize | Check if BIN input, if not, use PPF')}
         if ('inBin' in argv) {
           // If is not an in-place randomization, apply writes to the buffer
           // containing the disc image bytes.
@@ -1226,16 +1300,19 @@ if ('inBin' in argv) {
           fs.writeFileSync(argv.out, patch)
         }
       }
+      if ('debug' in argv) {console.log('randomize | function: randomize | Write error detection')}
       // Write error detection codes.
       if (fd) {
         eccEdcCalc(fd, size, true)
       }
+      if ('debug' in argv) {console.log('randomize | function: randomize | Output BIN')}
       // Write randomized bin.
       if (typeof(fd) === 'object') {
         fs.writeFileSync(argv.out, fd)
       }
     }
   } finally {
+    if ('debug' in argv) {console.log('randomize | function: randomize | Wrap-up')}
     if (typeof(fd) === 'number') {
       fs.closeSync(fd)
     }
diff --git a/src/util.js b/src/util.js
index db945f1..d865d21 100644
--- a/src/util.js
+++ b/src/util.js
@@ -1710,11 +1710,16 @@
           randomize.push('9')
         }
         delete options.fastwarpMode
-      } else if ('noprologueMode' in options) { // quickensd the teleporter warp animations - eldrich
+      } else if ('noprologueMode' in options) { // Removes prologue - eldrich
         if (options.noprologueMode) {
           randomize.push('R')
         }
         delete options.noprologueMode
+      } else if ('debugMode' in options) { // Debug mode - eldrich
+        if (options.debugMode) {
+          randomize.push('D')
+        }
+        delete options.debugMode
       } else if ('preset' in options) {
         randomize.push('p:' + options.preset)
         delete options.preset
@@ -2933,6 +2938,7 @@
     iwsMode,
     fastwarpMode,
     noprologueMode,
+    debugMode,
     mapcolorTheme,
     writes,
   ) {
@@ -2958,6 +2964,7 @@
     this.iwsMode = iwsMode
     this.fastwarpMode = fastwarpMode
     this.noprologueMode = noprologueMode
+    this.debugMode = debugMode
     this.mapcolorTheme = mapcolorTheme
     if (writes) {
       this.writes = writes
@@ -3096,6 +3103,8 @@
     this.fastwarp = false
     // No Prologue mode.
     this.noprologue = false
+    // No Prologue mode.
+    this.debug = false
     // Arbitrary writes.
     this.writes = undefined
   }
@@ -4714,6 +4723,7 @@
     const iws = self.iws
     const fastwarp = self.fastwarp
     const noprologue = self.noprologue
+    const debug = self.debug
     const writes = self.writes
     return new Preset(
       self.metadata.id,
@@ -4739,6 +4749,7 @@
       iws,
       fastwarp,
       noprologue,
+      debug,
       writes,
     )
   }