HP: We will be rolling HP per my standard rules: you may reroll any HP roll once, but must take the second roll. That means if you roll a 3 on a d10 for lvl 4, you may choose to reroll it. If you get a 1, you're stuck with the 1. If you get a 10, you made out like a bandit.

Critical Hits: This is an Epic campaign! No one wants to roll a critical and have it deal 4 damage. When you roll a critical hit (either with a spell or weapon attack), the first dice is maximized. That includes all damage dice for the weapon, such as sneak attack, hex, hunter's mark, elemental effects, and multiple dice such as the greatsword's 2d6. From there, you roll normal critical damage manually.

Long Rests: 5e is notorious for people shrugging off death by sleeping for a few hours. To help create incentive for downtime, make multiple-day fights a possibility, and in general make everything cooler, you will not regain maximum HP at the end of a long rest automatically. You can expend hit dice during a long rest to heal, or you can cast spells or use other abilities before the rest is complete, and per normal rules, you regain half your hit die on completion of a long rest. Enemies follow the same rules. As such, please keep careful track of your hit die on your sheet (Dicecloud has a good spot for it, or you can add them at the top of the features section in Myth-weavers).

Combat Posting: Combat will be done as I have in my other D&D campaigns. Typical format is a DM post with the initiative and combat map, then each PC gets 1-2 short paragraphs with the description of their actions, followed by a tidy note that has rolls, damage, and any other effects that are important to know. Combat should proceed quickly, and reactions to things that happen in combat can be done in a post following the combat. If these rules do not suit your fancy, this might not be the RP for you, as combat will be an important part. I don't want to hold up the party for someone to write 6 paragraphs over the course of a week while another character is making death saves. Here is an example of how I plan to do combat.

Epic Level Boons: Your maximum stat in any attribute is your character level (unless you have a feature or item that increases your cap). Under no circumstances will any attribute be allowed to exceed 30, including items and other features. At each even level, you may choose to either take an Epic Boon per the DMG (pg 230ish) or take a feat/ability score increase (+2 to one, or +1 to two separate stats). The feats or boons you choose must make sense with your PC. This is in addition to the standard increases you get from your level, including feats.

Magic Item Costs: The following are a list of items by rarity. Consumables are fifth cost. This is ONLY for buying starting items. Any gear (armor, weapons, etc) must add the cost of the gear to the cost listed below.
Common Magic Items: 100 gp
Uncommon Magic Items: 500 gp
Rare Magic Items: 5,000 gp
Very Rare Magic Items: 50,000 gp
Legendary: Some things are priceless. For everything else, there's Mastercard.

Proficiency Bonus: PB increases by 1 at level 21, 25, and 29.

Extra Attack: If you multiclass into two classes that give you Extra Attack (and have reached the appropriate level in each), at level 25, you gain Extra Attack (2) per the Fighter feature. This does not stack with levels in Fighter (meaning you will not get 5 attacks), but it does stack with Thirsting Blade and other similar features.