Are there coammnds that do this:
If you make a TNT or a Minecart with TNT in the INV that it is deleted and there's no message in the chat
A title that always comes when you start a new joint
Yes and yes.
For 1:
Place two command blocks that are executed one after the other. First here:
/ execute as @a [nbt = {Inventory: [{id: "minecraft: tnt"}]}]] run say The message
Then this one:
/ execute as @a [nbt = {Inventory: [{id: "minecraft: tnt"}]}]] run clear @s minecraft: tnt
The same for minecraft: tnt_minecart instead of minecraft: tnt
For 2:
Create a scoreboard called left:
scoreboard objectives add left minecraft.custom: minecraft.leave_game
And then make 4 command blocks that are executed every tick. (Each line belongs in a command block):
scoreboard players set @a [tag =! JoinedBefore] left 1
title @a [scores = {left = 1}] title {"text": "Hello!"}
tag @a [tag =! JoinedBefore] add joinedBefore
scoreboard players reset @a left
Instead of "Hello" hold the title you want to display.
The commands don't go with me. I'm 1.8.8
Then please write that in the question, I've waited 10 minutes for it…
Sorry… Next time you can do it anyway would be mega nice
For 1:
Simply delete in a continuous loop TNT:
/ clear @a tnt 0
And I think with a comparator you can detect whether the command block has executed the command. You then route the signal of the comparator into a second command block with "say the message"
Yes, that's good then please with tnt minecart and the title that would be very nice!
/ clear @a tnt_minecart 0
And for that with the title:
Create a scoreboard like this:
/ scoreboard objectives add quits stat.leaveGame
Write this in a repeating command block:
/ execute as @a [scores = {quits = 1.}] at @s run title @a title {"text": "your text"}
In a chain command block, in the direction in which the first command block points:
/ scoreboard players set @a [scores = {quits = 1.}] quits 0
That with the title is not possible because there are no chains in 1.8 and no @s and tnt_minecart are not possible either
Then instead of @s ~ ~ ~, instead of Chains comparator and instead of tnt_minecart MinecartTNT
You can do this with the command / clear @a tnt (I haven't heard it yet) or with plugins.