An important part of generating a DASH seed is the random creation of the Item Pool: the list of items to be placed in the game. Generally speaking, the Item Pool is divided into two item categories: Majors (Morph Ball, Gravity Suit, Energy/Reserve Tanks, etc.) and Minors (Missiles, Super Missiles, and Power Bombs). Major Items in the Item Pool can be affected by both the chosen Item Split and Extra DASH Items.
The Item Split determines the valid locations where major items can be placed. DASH currently offers three Item Split options: Major/Minor, Recall Major/Minor, and Full.
Major items can be placed at any of the vanilla major item locations. For balance, the Energy Tank location at HiJump Boots is considered a minor location and the Right Side Super Missile location in Wrecked Ship is considered a major location.
Similar to normal Major/Minor with a few tweaks. Mickey Mouse Missiles, Watering Hole Supers, and Sky Missiles are now considered major item locations. Kraid Energy Tank is considered a minor item location.
Any location can hold a major item.
Extra DASH Items
DASH introduces new major items which can optionally be included in the item pool. This includes Double Jump, Heat Shield, Pressure Valve, and Charge Upgrades for certain Beam Modes.
Building Item Pools
This is the process followed when building an item pool:
Add one of every vanilla item type to the item pool except for Charge Beam (all vanilla majors, 1 energy tank, 1 reserve tank, 1 missile, 1 super missile, 1 power bomb)
Either add Charge Beam to the item pool or the appropriate number of Charge Upgrades based on the Beam Mode
Add any extra DASH items to the pool (Double Jump, Heat Shield, or Pressure Valve)
Add energy tanks and reserve tanks based on the Item Split
Full - Add 14 energy tanks and 4 reserve tanks
Major/Minor - With only 34 major locations, we limit the number of energy and reserve tanks to fit. We want to place all 14 energy tanks so we initially reduce the number of reserve tanks down to a minimum of 2. We then add energy tanks until we have exactly 34 major items in the pool.
Recall Major/Minor - In general, this Item Split works like normal Major/Minor but with 36 major item locations. However, it is possible that we may end up with less than 36 major items even with 4 reserve tanks and 14 energy tanks. In that case, Super Missile packs are added as major items.
Add minor items to the item pool based on the selected ratio (3:2:1 or 2:1:1) until there are 100 items. Given a 3:2:1 ratio, every item added to the pool has a 3/6 chance of being a missile, 2/6 chance of being a super, and 1/6 chance of being a power bomb.