MFMods

when you change the build.gradle, a small hard-to-notice floating window shows up in intellij idea - above editor, close to the right side. try increasing the version in build.gradle if that's where you keep it. then click the button with two arrows forming a circle and grab an apple. in about 5 minutes, your access transformer lines will be applied (assuming you uncommented the AT line in build.gradle).

do not use mixins for this. maybe you'll need access transformers for some fields (where the zombie is trying to walk to) but you do not need mizins. respond to "entity joins world". add your ai goal to zombies list of goals.

you do realize we have no idea what you wrote and where? also, even if you did it right, maybe a code from one of the goals is changing y-rotation after your code. read through all the goals that are active. delete all goals unless they meet two requirements: 1) you want the goal to execute, and 2) you 100% understand everything it does.

there is a simple answer to your optifine problem: do not use optifine. trust me on this, because it is highly unlikely your computer is older than mine. i need performance mods more than you do. rubidium plus canary. remove optifine, put those two and you're good. for a good measure, add a few minor performance mods too, clumps and maybe something that culls leaves (depending on the way you play).

can you make it change sprite depending on condition (like clock or a bow)? once you have that, having one piece of png file transparent should do the job. disclaimer: haven't tried.

if the idea requires mathematical knowledge that you do not have (working with angles) and programming skills you do not have (skipping math and finding a way to reuse existing projectile logic), why are you still working on this mod? surely you can come up with a mod idea without impassable barriers.

hmm... so make a stack, okay, set the tag, okay (i'll just assume you tried that), then disregard the stack you made, make a new one without tag and put in into drops... might work...

nope.

what do you need? if you need to know the type of block (which the title implies "Check if block at given position is grass/foliage/water"). try the isReplaceable method or compare the block material with something. if you need the color... those green stuff are usually gray (in png files) and those textures (in models) are assigned tint indexes. then, the developer tells the game how to recolor these parts of the model. the problem for you is - there is more than one way to choose a tint color.

well trident has a separate texture for inventory. i can't say more without making a test mod, nor can others. if you give us a github link, maybe someone will be able to say more. general hint: if you need to adjust the item variants (1st person left, 1st person right hand, on ground, inventory, 3rd person...) get a mod called "itemtransformhelper" and do it in-game, then paste into your json. mostly useful for blocks and occasional weapon.

that gui window closing is a developer's decision, not a necessity. so yes, it is possible. however, to change that, you either have to ask the author to make a change or you can change the mod yourself (if license permits and it almost certainly does).

we don't help with 1.16 anymore, but this is a problem unrelated to the version so i'll tell you what to do... did you look at the log you pasted? doesn't matter that you're not a programmer. just look for mod identifiers. usually in namespaces (something-dot-something-dot-mod_id). in this case the crash is in first few lines and mentions a mod family. remove them or update them or contact author.

2) just separate "forge" stuff (registering things, etc.) from "mod" stuff (what should happen for players to see) into separate classes and you will be fine. 3) no, not really. especially if you want to port to other mod loaders. except maybe architectury but i never used that. 4) don't worry about it, at least for controllable things like chickens. let player decide if he wants 4 or 400 chickens around. you should worry about ambient entities (things flying/swimming around) and not have hundreds of those especially if you can't prevent them from appearing all the time (like squids) or if you can't kill them (like some glowbugs/fireflies...). 1) start with 1.18. porting to 1.19 is pretty easy, but you probably wont want to maintain 1.19 in parallel, likely 1.18 and 1.20. you do not need to decide on this now because you don't know when you'll have a stable mod and free time.

are you using a vanilla Tier or your own? if you made a new tier for it (passed in constructor), you can just specify the tool speed there (see Tiers enum, third parameter in Tier constructor); not the same as attack speed which is in item constructor.

hold on. do not do both 1 and 2. do variant 2. annotation on class, annotation on event handler method, make method static. you do not want events to trigger twice.