I don't really know if harvest scythes is causing the crash, or something else.

---- Minecraft Crash Report ----
// Hi. I'm Minecraft, and I'm a crashaholic.

Time: 1/1/21 3:45 AM
Description: Initializing game

java.lang.RuntimeException: Could not execute entrypoint stage 'main' due to errors, provided by 'harvest_scythes'!
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke0(EntrypointUtils.java:53)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke(EntrypointUtils.java:36)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointClient.start(EntrypointClient.java:32)
at net.minecraft.class_310.(class_310.java:437)
at net.minecraft.client.main.Main.main(Main.java:177)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:224)
at net.fabricmc.loader.launch.knot.Knot.init(Knot.java:141)
at net.fabricmc.loader.launch.knot.KnotClient.main(KnotClient.java:27)
Caused by: java.lang.NoSuchFieldError: TANTALITE
at wraith.harvest_scythes.support.MythicMetalsSupport.loadItems(MythicMetalsSupport.java:48)
at wraith.harvest_scythes.HarvestScythes.onInitialize(HarvestScythes.java:31)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointClient$$Lambda$2548/2103311527.accept(Unknown Source)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke0(EntrypointUtils.java:50)
... 11 more

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Thread: Render thread
Stacktrace:
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke0(EntrypointUtils.java:53)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke(EntrypointUtils.java:36)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointClient.start(EntrypointClient.java:32)
at net.minecraft.class_310.(class_310.java:437)

-- Initialization --
Details:
Stacktrace:
at net.minecraft.client.main.Main.main(Main.java:177)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:224)
at net.fabricmc.loader.launch.knot.Knot.init(Knot.java:141)
at net.fabricmc.loader.launch.knot.KnotClient.main(KnotClient.java:27)

-- System Details --
Details:
Minecraft Version: 1.16.4
Minecraft Version ID: 1.16.4
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1194013608 bytes (1138 MB) / 2986344448 bytes (2848 MB) up to 5368709120 bytes (5120 MB)
CPUs: 6
JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx5G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
Fabric Mods:
adorn: Adorn 1.12.2+1.16.4
advanced_runtime_resource_pack: Runtime Resource Pack 0.2.9
advancements-enlarger: Advancements Enlarger 0.2.3
advdebug: Advancements Debug 2.2.0
adventurez: AdventureZ 1.1.5
amecsapi: Amecs API 1.1.1+mc1.16-rc1
angerable-patch: Angerable Patch 1.1.0-1.16.4
architectury: Architectury 1.2.65
arstheurgia: Ars Theurgia 1.0.5
artifacts: Artifacts 2.0.2+1.16.4-fabric
artifice: Artifice 0.13.1+1.16.2-rc1
artofalchemy: Art of Alchemy: Memoriam 1.0.0-rc4+1.16.4
astromine: Astromine 1.11.4+fabric-1.16.3
astromine-core: Astromine: Core 1.11.4+fabric-1.16.3
astromine-discoveries: Astromine: Discoveries 1.11.4+fabric-1.16.3
astromine-foundations: Astromine: Foundations 1.11.4+fabric-1.16.3
astromine-technologies: Astromine: Technologies 1.11.4+fabric-1.16.3
astromine-transportations: Astromine: Transportations 1.11.4+fabric-1.16.3
atbyw: All The Blocks You Want (ATBYW) 1.3.4
autoconfig1u: Auto Config v1 Updated 3.3.1
backslot: BackSlot 1.1.8
bambootweaks: Bamboo Tweaks unspecified
battletowers: Battle Towers 3.3.1-beta-1.16.4
bebooks: Better Enchanted Books 1.1.4
bedspreads: Bedspreads 1.3.1-1.16.4
bettercaves: YUNG's Better Caves 1.16.2-1.0.3
betterend: Better End 0.8.4-beta
bettermineshafts: YUNG's Better Mineshafts 1.16.4-1.0
betternether: Better Nether 5.0.4
biomemakeover: Biome Makeover 1.16.4-1.1.6
blade: Blade 2.0.0
blast: BLAST 1.5
blockus: Blockus 2.0.1+1.16.4
blue_endless_jankson: jankson +
borderlessmining: Borderless Mining 1.0.6+1.16.2
byg: BYG 1.1.3
cameraoverhaul: Camera Overhaul 1.0.1-fabric-1.16
campanion: Campanion 1.3.1+build.51
can-i-mine-this-block: cAn i MiNe thIS bLOCk? 1.0.2
cardinal-components: Cardinal Components API 2.7.10
cardinal-components-base: Cardinal Components API (base) 2.7.10
cardinal-components-block: Cardinal Components API (blocks) 2.7.10
cardinal-components-chunk: Cardinal Components API (chunks) 2.7.10
cardinal-components-entity: Cardinal Components API (entities) 2.7.10
cardinal-components-item: Cardinal Components API (items) 2.7.10
cardinal-components-level: Cardinal Components API (world saves) 2.7.10
cardinal-components-scoreboard: Cardinal Components API (scoreboard) 2.7.10
cardinal-components-util: Cardinal Components API (utilities) 2.7.10
cardinal-components-world: Cardinal Components API (worlds) 2.7.10
carrier: Carrier 1.6.1
cavebiomes: Cave Biomes 0.5.1
ce_foodstuffs: Common Expansion: Foodstuffs 1.1.2
chainmail: Chainmail 0.5.0
charm: Charm 2.2.1
charmonium: Charmonium 2.2.0
chunkpregen: Fabric Chunk Pregenerator 0.3.3
cinderscapes: Cinderscapes 1.3.0+build.51
cleancut: CleanCut mc1.16-2.1-fabric
cloth-armor-api-v1: Cloth Armor API v1 1.4.8
cloth-basic-math: Cloth Basic Math 0.5.1
cloth-client-events-v0: Cloth Client Events v0 1.4.9
cloth-common-events-v1: Cloth Common Events v1 1.4.8
cloth-config2: Cloth Config v4 4.8.3
cloth-datagen-api-v1: Cloth Datagen v1 1.4.8
cloth-durability-bar-api-v1: Cloth Durability Bar API v1 1.4.8
cloth-dynamic-registry-api-v1: Cloth Dynamic Registry API v1 1.4.8
colorfulcolumns: Colorful Columns 1.0.0
columns: Columns 1.1.1
com_electronwill_night-config_core: core 3.6.2
com_electronwill_night-config_toml: toml 3.6.2
com_github_therandomlabs_trlutils-config: TRLUtils-Config master-SNAPSHOT
com_github_therandomlabs_trlutils-fabric: TRLUtils-Fabric 1.16-SNAPSHOT
com_moandjiezana_toml_toml4j: toml4j 0.7.2
compressedblocks: Compressed Blocks 1.0
controlling: Controlling For Fabric 1.1.2
couplings: Couplings 1.3.3
crowdin-translate: CrowdinTranslate 1.2
crumbs: Crumbs 1.0.6
cspirit: Christmas Spirit 1.0.0+mc.1.16.4
curios: Curios API 0.0.10-1.16.3
customportalapi: customportalapi 0.0.1-beta18-1.16
darkpaintings: Dark Paintings 2.0.0
dawn: Dawn API 1.6.1
desolation: Desolation 1.0.3
diggusmaximus: Diggus Maximus 1.4.2-1.16.3
disable_custom_worlds_advice: Disable Custom Worlds Advice 1.2
discontinuous_beacon_beams: Discontinuous Beacon Beams 1.0+MC1.16.2-1.16.4
dyetherite: Dyetherite 1.0.0+1.16.4
dynamicfps: Dynamic FPS 1.1.4
eggtab: Egg Tab 1.3.2+1.16-fabric
enchantment_lore: EnchantmentLore 1.1+MC1.16.1-1.16.4
enderitemod: Enderite Mod 1.2.2
expandedstorage: ExpandedStorage 5.6.31
ezpas: Ezpas 1.2.3-1.16.2
fabric: Fabric API 0.29.0+1.16
fabric-api-base: Fabric API Base 0.2.0+ab87788d3a
fabric-biome-api-v1: Fabric Biome API (v1) 3.1.0+2e23b97c3a
fabric-blockrenderlayer-v1: Fabric BlockRenderLayer Registration (v1) 1.1.4+c6a8ea8995
fabric-command-api-v1: Fabric Command API (v1) 1.0.9+6a2618f53a
fabric-commands-v0: Fabric Commands (v0) 0.2.1+cbe9176f3a
fabric-containers-v0: Fabric Containers (v0) 0.1.9+a03e98793a
fabric-content-registries-v0: Fabric Content Registries (v0) 0.2.0+e77439c73a
fabric-crash-report-info-v1: Fabric Crash Report Info (v1) 0.1.2+b7f9825d3a
fabric-diagonal-panes: Fabric Diagonal Panes 0.4.0
fabric-dimensions-v1: fabric-dimensions-v1 2.0.1+9a6c75813a
fabric-entity-events-v1: Fabric Entity Events (v1) 1.0.0+79b23bee3a
fabric-events-interaction-v0: Fabric Events Interaction (v0) 0.4.1+6a2618f53a
fabric-events-lifecycle-v0: Fabric Events Lifecycle (v0) 0.2.0+16acbe5b95
fabric-furnaces: Fabric Furnaces 1.3.2-1.16.2
fabric-game-rule-api-v1: Fabric Game Rule API (v1) 1.0.5+cbe9176f3a
fabric-item-api-v1: Fabric Item API (v1) 1.2.0+6a2618f53a
fabric-item-groups-v0: Fabric Item Groups (v0) 0.2.2+cbe9176f3a
fabric-key-binding-api-v1: Fabric Key Binding API (v1) 1.0.1+730711c63a
fabric-keybindings-v0: Fabric Key Bindings (v0) 0.2.0+3fa9f7c595
fabric-language-kotlin: Fabric Language Kotlin 1.4.21+build.1
fabric-lifecycle-events-v1: Fabric Lifecycle Events (v1) 1.2.0+74cc3b2095
fabric-loot-tables-v1: Fabric Loot Tables (v1) 1.0.1+6a2618f53a
fabric-mining-levels-v0: Fabric Mining Levels (v0) 0.1.2+b764ce9995
fabric-models-v0: Fabric Models (v0) 0.2.0+cbe9176f3a
fabric-networking-api-v1: Fabric Networking API (v1) 1.0.0+4358fbc63a
fabric-networking-blockentity-v0: Fabric Networking Block Entity (v0) 0.2.7+a03e98793a
fabric-networking-v0: Fabric Networking (v0) 0.3.1+2a4333d33a
fabric-object-builder-api-v1: Fabric Object Builder API (v1) 1.9.2+6a2618f53a
fabric-object-builders-v0: Fabric Object Builders (v0) 0.7.1+6a2618f53a
fabric-particles-v1: Fabric Particles (v1) 0.2.3+cbe9176f3a
fabric-registry-sync-v0: Fabric Registry Sync (v0) 0.7.3+be155ae23a
fabric-renderer-api-v1: Fabric Renderer API (v1) 0.4.0+cbe9176f3a
fabric-renderer-indigo: Fabric Renderer - Indigo 0.4.3+6a2618f53a
fabric-renderer-registries-v1: Fabric Renderer Registries (v1) 2.2.0+f8ac1db23a
fabric-rendering-data-attachment-v1: Fabric Rendering Data Attachment (v1) 0.1.4+6a2618f53a
fabric-rendering-fluids-v1: Fabric Rendering Fluids (v1) 0.1.12+6a2618f53a
fabric-rendering-v0: Fabric Rendering (v0) 1.1.1+6a2618f53a
fabric-rendering-v1: Fabric Rendering (v1) 1.5.0+c26373133a
fabric-resource-loader-v0: Fabric Resource Loader (v0) 0.4.0+552549d53a
fabric-screen-handler-api-v1: Fabric Screen Handler API (v1) 1.1.0+6a2618f53a
fabric-structure-api-v1: Fabric Structure API (v1) 1.1.3+cbe9176f3a
fabric-tag-extensions-v0: Fabric Tag Extensions (v0) 1.1.0+e77439c73a
fabric-textures-v0: Fabric Textures (v0) 1.0.5+a4467d2a3a
fabric-tool-attribute-api-v1: Fabric Tool Attribute API (v1) 1.2.5+6a2618f53a
fabricloader: Fabric Loader 0.10.8
farsighted-mobs: Farsighted Mobs 1.0a
fatxporbs: Fat Experience Orbs 0.0.9
fermion: Fermion 2.1.191
fermion-modkeys: Fermion Modifier Keys 1.8.180-snapshot
fiber: fiber 0.23.0-2
flamingo_ooo: Flamingo, oh, oh, oh... 1.0.4-MC1.16.3-fabric
flonters: Flonters 1.1.1+1.16.2
frex: FREX 3.4.140
gameinfo: GameInfo 1.5.4 1.16.4
geckolib: Geckolib 2.0.0
gentlefawn: GentleFawn 1.1.2-MC1.16.3-fabric
givemehats: Give Me Hats! 1.4
glassdoor: Glass Doors 1.5.0-1.16
glassential: Glassential 1.16.4-1.1.5
gobber2: Gobber2 2.3.38
greater_eye: Greater Eye of Ender 1.1.4
harvest_scythes: Harvest Scythes 1.0.6
healthoverlay: Health Overlay 3.6.13
hookshot: Hookshot 10.0
horseinfo: Horse Info 0.2.2-1.16.1
hotm: Heart of the Machine 1.16.3-0.1.7
howlingwolves: Howling Wolves 1.0.0+build.1
ignis-fatuus: Ignis Fatuus 1.1.0
improved-stations: Improved Stations 2.0.3
indrev: Industrial Revolution 1.7.15-BETA
indypets: Independent Pets 0.2.0
inmis: Inmis 1.3.1-1.16.2
inventorysorter: Inventory Sorter 1.7.4-1.16
jankson: Jankson 3.0.1+j1.2.0
json-model-extensions: JSON Model Extensions 1.15.127
jumpoverfences: JumpOverFences 1.16-0.0.3
kibe: Kibe 1.6-BETA
kirin: Kirin UI 1.7-1.16.2
kubejs: KubeJS 1.5.5
kykinite: Kykinite 1.1.4
kyrptconfig: Kytpt Config 1.1.6-1.16
lamps: The Lamps! 1.0
lapisreserve: Lapis Reserve 1.0.6
libblockattributes: LibBlockAttributes 0.8.4
libblockattributes_core: LibBlockAttributes (Core) 0.8.5
libblockattributes_fluids: LibBlockAttributes (Fluids) 0.8.5
libblockattributes_items: LibBlockAttributes (Items) 0.8.4
libcd: LibCapableData 3.0.3+1.16.3
libgui: LibGui 3.2.2+1.16.3
libstructure: LibStructure 1.5
lightoverlay: Light Overlay 5.5.4
lightstones: Lightstones 1.2
llamasteeds: Llama Steeds 2020.2.8
magna: Magna 1.4.3-1.16.2
malilib: MaLiLib 0.10.0-dev.21+arne.2
mcda: MC Dungeons Armors 0.8.5
mcdw: MC Dungeons Weapons 2.3.5
megane: megane 3.1.1+1.16.4
megane-api: megane-api 3.1.1+1.16.4
megane-impl: megane-impl 3.1.1+1.16.4
megane-runtime: megane-runtime 3.1.1+1.16.4
minecraft: Minecraft 1.16.4
mm: Manningham Mills 2.1
mo_glass: Mo Glass 1.5-MC1.16.4
modern_industrialization: Modern Industrialization 0.3.9
modid: Damage Tilt 1.16-fabric-0.1.0
modmenu: Mod Menu 1.14.13+build.19
moretotems: More Totems 2.7.1
mostructures: Mo' Structures 1.0.1+mc.1.16.4
mousewheelie: Mouse Wheelie 1.6.1+mc1.16.4
musicdr: Music Duration Reducer 1.1.3
mythicmetals: Mythic Metals 0.9.8
no-potion-offset: No Potion Offset ${version}
nookbuild: NookBuild 1.2.1
org_codehaus_groovy_groovy: groovy 3.0.3
org_codehaus_groovy_groovy-jsr223: groovy-jsr223 3.0.3
org_jetbrains_annotations: annotations 20.0.0
org_jetbrains_kotlin_kotlin-reflect: kotlin-reflect 1.4.21
org_jetbrains_kotlin_kotlin-stdlib: kotlin-stdlib 1.4.21
org_jetbrains_kotlin_kotlin-stdlib-jdk7: kotlin-stdlib-jdk7 1.4.21
org_jetbrains_kotlin_kotlin-stdlib-jdk8: kotlin-stdlib-jdk8 1.4.21
org_jetbrains_kotlinx_kotlinx-coroutines-core-jvm: kotlinx-coroutines-core-jvm 1.4.2
org_jetbrains_kotlinx_kotlinx-coroutines-jdk8: kotlinx-coroutines-jdk8 1.4.2
org_joml_joml: joml 1.9.25
org_yaml_snakeyaml: snakeyaml 1.26
packages: Packages 1.1.1
parakeetmod: The Parakeet Mod 1.16.3-1.0.6
patchouli: Patchouli 1.16.4-48-FABRIC
piglib: Piglib 1.0.1
plantusmaximus: Plantus Maximus 1.0.0-1.16.4
playerabilitylib: Pal 1.2.1
pling: Pling 1.3.0
presencefootsteps: Presence Footsteps r29+1.16.4
queks_end: Quek's End 1.1
quickshulker: Quick Shulker 1.1.11-1.16
reach-entity-attributes: Reach Entity Attribute 1.0.1
reborncore: Reborn Core 4.6.2+build.108
repurposed_structures: Repurposed Structures 1.16.4-1.7.3
roughlyenoughitems: Roughly Enough Items 5.8.10
roughlyenoughitems-api: REI (API) 5.8.10
roughlyenoughitems-default-plugin: REI (Default Plugin) 5.8.10
roughlyenoughitems-runtime: REI (Runtime) 5.8.10
sakurarosea: Sakura Rosea 1.6.0-MC1.16.3-fabric
seasons: Fabric Seasons 1.0.3-BETA
shapes: Shapes 2.0.0+build.10
shulkerboxtooltip: Shulker Box Tooltip 2.3.3+1.16.4
simpleteleporters: Simple Teleporters 2.2.0
simplyplatinum: Simply Platinum 2.1
slight-gui-modifications: 'Slight' GUI Modifications 1.6.1
slotlock: SlotLock 1.0.1-BETA
staffofbuilding: Staff of Building 1.2.4-1.16.2
static-content: Static Content 1.0.1-1.16.2
staticdata: Static Data 1.1.2
step-height-entity-attribute: Step Height Entity Attribute 1.0.0
stopstridersuffering: Stop Strider Suffering 1.0.1-mc1.16.4-fabric
strawdummy: Straw Dummy 1.4.0
structure-helpers: Structure Helpers 3.0.0
tacocraft: TacoCraft 1.3.1+mc.1.16
team_reborn_energy: Energy 0.1.1
techreborn: Tech Reborn 3.7.2+build.189
terraform-biome-builder-api-v1: Terraform Biome Builder API (v1) 1.0.0+build.1
terraform-config-api-v1: Terraform Config API (v1) 1.0.0+build.1
terraform-dirt-api-v1: Terraform Dirt API (v1) 1.0.0+build.1
terraform-overworld-biome-extensions-api-v1: Terraform Overworld Biome Extensions API (v1) 1.0.0+build.1
terraform-shapes-api-v1: Terraform Shapes API (v1) 1.0.0+build.4
terraform-surfaces-api-v1: Terraform Surfaces API (v1) 1.0.0+build.1
terraform-tree-api-v1: Terraform Tree API (v1) 1.0.1+build.4
terraform-wood-api-v1: Terraform Wood API (v1) 1.0.0+build.1
terrestria: Terrestria 2.1.5+build.28
the_bumblezone: The Bumblezone - Fabric 1.16.3-2.2.13
tk_valoeghese_zoesteriaconfig: ZoesteriaConfig 1.3.2
totemmod: Wither Totems Mod 0.3.2
trapexpansion: Trap Expansion 1.3.2
traverse: Traverse 3.2.0+build.17
trinkets: Trinkets 2.6.7
truerooms: True Secret Rooms 1.1.2-hotfix
tweakeroo: Tweakeroo 0.10.0-dev.20201110.132827
tweed: Tweed API 3.0.0-beta.22
unearthed: Unearthed 1.0.5
universalcomponents: Universal Components 0.7.3+1.16.2
unsaddlepigs: Unsaddle Pigs 1.0.1-mc1.16.4-fabric
upstream: Upstream 1.0.1
vanilla-hammers: Vanilla Hammers 3.0.1-1.16.3
vanilladeathchest: VanillaDeathChest 1.16.3-1.11.0.7-fabric
vanillaexcavators: Vanilla Excavators 1.1.0
villagerhats: Villager Hats fabric-1.16.4-1.0.1
villagernames: Villager Names 1.6.0
voyager: Voyager 1.0.0
waila: Hwyla 1.9.22
waystones: Waystones 1.0.10
wild_explorer: Wild Explorer 1.3.1
wolveswitharmor: Wolves With Armor 1.5.2-1.16.2
woodenhoppers: Wooden Hoppers 1.0.0
woods_and_mires: Woods and Mires 1.0.4+1.16.3
wrenchable: Wrenchable 1.0.0+1.16.1
yosbr: YOSBR 0.1.0
yungsapi: YUNG's API 1.16.4-Fabric-1
zoob: Monster Of The Ocean Depths 2.5.0
Patchouli open book context: n/a
Launched Version: fabric-loader-0.10.8-1.16.4
Backend library: LWJGL version 3.2.2 build 10
Backend API: NO CONTEXT
GL Caps:
Using VBOs: Yes
Is Modded: Definitely; Client brand changed to 'fabric'
Type: Client (map_client.txt)
CPU:

Use the latest version of MythicMetals (0.9.9-snapshot or higher)
https://www.curseforge.com/minecraft/mc-mods/mythicmetals/files/3153510

The creator of MythicMetals has deleted the snapshot builds since he made official releases. Just use the latest version of MythicMetals and you're good to go.

Use the latest version of MythicMetals (0.9.9-snapshot or higher)
https://www.curseforge.com/minecraft/mc-mods/mythicmetals/files/3153510

link not found