High tide 5e v1: for disrespecting the rules

Group intative:

In some situations, players may have to work together to take down enemies, whether it's vechicles or just normal fights, players do have the option to use group inative as do enemies. (In vechicle combat, such as boat or horseback, they are stuck into this unless they leave their vechicle). In group inative, everyone in the group pools their rolls together to a maximum of the smallest group's total members (in a 5 v 3, 3 rolls would be added). The group with the highest total goes first, and group attacks happen all at once, the player with the highest roll states their attack first however. Players who choose to not group up for combat continue as normal, going either before or after the group. If two or more group members attack the same target, all attacks gain a damage bonus and lose a to hit bonus equal to how many attackers there are. Grouped up allies DO NOT need to attack the same target or even on their turn, they still have access to all their normal abilities and things such as healing spells and item uses, which still happens the same as an action, and movement is taken together too if players head in the same direction.

Surprise reactions:

Oh no, you've been hit! You're barely holding on and they've still got one attack left! Why not cut them off? Yep, surprise reactions. If you choose to attempt one, you first need to make a wisdom save at a DC equal to the roll to hit you. (If they rolled a 15, you have to roll 15 or higher to surprise react). As a surprise reaction, you can stop the intiative and take an action as if it were your turn instead! You make an action and intative continues as if nothing happened afterwards, allowing you the chance to back away from an enemy, heal yourself, or strike that bastard down!Moving during a surprise reaction does not provoke opportunity attacks as long as you're moving away from an enemy (moving into their range or sideways can still get you hit). Disrespect the rules, make your own! But be careful, failing on your check gives the enemy that just attacked you a surprise reaction instead, so use this new found power wisely!

Tag teaming, what it is and what you can do:

You and your friend are exploring a cave together when suddenly, bam, spider. Your health quickly drops and your friend has healing spells, but they're not using them because they don't want to lose their attack for that turn. Tell me, have you seen something like that happen? Maybe what they need is more time to do what they need to do! Well, with high tide, all you have to say is "I tag the healer in!" You can tag team with anyone you can see who can see you, but what even is tag teaming? Tag teaming allows you to give up your actions for your turn and instead give that to someone else as soon as you end your turn. You are still able to move as normal but you give up all bonus actions so you cannot dash. Reactions and surprise reactions are still available, and you can tag team during a surprise reaction! You must do this before using any actions and if you have more than one, you can still use them.

What are the benefits of a tag team? When making an attack, you gain a flat +2 to hit bonus and any healing done does an extra 1d4 healing on a tag teamed turn. Any spells that require a roll also gain the bonus (does not stack for spell attacks). It also mixes up inative similar to how suprise reactions do, instead triggering after the players turn instead of after an attackers turn. After that, buisness as usual.

Berserker rounds:

So you made a big boss, mean guy. You want him to do a lot of damage per round, but you also want it to be fair. Why not let it attack a bunch? Yep, berserker rounds, the enemy can use these however they like as long as it does damage. This can be casting spells, making melee or ranged attacks, or just making shit up! They simply need to do something that could do damage on that turn. Berserker rounds are different from multiattacks because they have different placements in the initative from the users base turn. This can be used to seriously up the amount of damage an enemy does without players noticing too much. Also consider giving raging barbarians berserker rounds instead of a damage bonus. The main application for this is NPC bosses, just so you're aware!