Timelords
A time-travel RPG with two campaign types: In one you play yourself¸ accidentally thrown from world to world by a strange device. In the other¸ you play members of a ""Time Patrol"" who fix kinks in the time lines caused by people like the former as well as intentional trouble-makers. It uses a detailed skill-based system¸ which uses roll d20 under skill value for success¸ but modifiers use a multiplicative chart rather than adding/subtracting (i.e. a +4 modifier adds 20% of your skill: changing 5 to 6¸ 10 to 12¸ etc.) Each skill has a learning rate determined by one or more attributes. For example¸ Survival is linked to Intelligence and Perception¸ while Music is linked to Intelligence¸ Perception¸ and Dexterity. Two other notable features: there is a system for rating yourself to determine the player's attributes; and there are no fixed hit points. - A description from https://darkshire.net/jhkim/rpg/encyclopedia/ with kind permission of John H. Kim"