After you have opened a position on Bitmex, lets say its up 100% on like 25x leverage. Not a lot invested originally, say $50. Now, if I were to increase my position to 100x (you know by dragging the button on the scroller, not talking about changing leverage with numerical input from the footer window) what happens to the liquidation mark, does it change liquidation to point to liquidation to Bitcoin's value at the current time or the time when positioned  was  opened but with the 100x margin liquidation levels?

Alternatively what happens were to make a deposit and buy more bitcoin shares from market, say another $20 or something just to mess around with. I'm very aware these margins are essentially gambling and what it is im doing. Even though im having a bit of fun I still want things tended to properly, so please help me understand. Sorry if my English was bad this is not my first language.