General rules:

• Every damage that comes from an enemy does count as a hit
• Blocking count as hit
• Every stagger is hit
• Bifrost does not count as hit or damage if this affliction isn't applied by an attack
• Tryfing relic is valid for hitless as you make damage to your self but is invalid for damageless
• Forsbrandr relic is valid for hitless and damageless
• The basic rage (fury) is valid for damageless and hitless but if you get hit with it invalidates hitless category
• The protector barrier buff is valid for damageless but if you get hit invalidates hitless category

*This is a recommendation, change the QTA settings, instead of pressing consecutively change it to hold the button, this will avoid the risk of getting hit or damaged in some points of the runs

Main game:

• At the start of the main game, freyja will appear and make a script damage, this is valid for hitless and damageless runs as you can't avoid it
• On the fight against Vanadis on the main game (Freyja) you will be damaged by her for the "valour" tutorial this is scripted damage so it doesn't count as hit

Valhalla DLC:

• If you quit out the game, the mid boss and the tyr bossfight will allways be the same, this is allowed, this means that you can decide which mid boss and tyr you will do in your run, but the rest of the rooms will be different instead of the "?" rooms that are allways the same
• Tyr grab does count as hit but not damage, if you fail the QTA he will damage you
• In Greace, some enemies link you, this might damage Kratos. Open the glifs menu to verify HP bar in case there's no damage received you can continue (damageless)
• Opening chest that damage you is only allowed for hitless runs.
• Opening chest that remove rage is valid for both hitless/damageless