Colossus Clamberer

You have a sharp eye for the movement-patterns of enemies much more massive than you, making it possible to climb along creatures that are significantly larger than you are with relative ease.

• If your hands are free you are able to scale any creature over the size of Large without halving your movement-speed. 
• If you hold one dagger or one dart in either hand, your climbing-speed is halved but you can cause half of your strength-modifier (at least 1) as piercing-damage for every five feet you scale. This does not require an attack-action but it does roll against the creatures AC minus its dexterity-modifier.
• None of this will not require a check of any kind unless the creature tries to get rid of you in any way. In this case, roll for athletics against the creatures athletics or acrobatics.
• You may be able to lodge a dagger, a dart, a large hook, a large nail or anything of similar make into the creature to give yourself advantage against being removed from its body. Roll a melee weapon attack against the creatures AC minus its dexterity modifier. This will require an action and additionally counts as a melee weapon attack. On a success you may roll your saving-throw with advantage.
• If the creatures AC is independent of it's dexterity modifier then the modifier must not be subtracted from it's AC.
• Movement-bonuses or -improvements of any kind do not interfere with this Feat.