Against mordekaiser, As soon as Mordekaiser activates his W, disengage as he will block the damage you deal to him if you continue to fight him.

Mordekaiser is quite immobile. If you keep the minion wave closer to your side of the map, you will force him to overextend for farm. You can then capitalise on this and get assistance from your Jungler.

Once Mordekaiser hits level 6, his kill pressure in lane grows. Keep this in mind and be wary with your positioning when low as he may try and catch you out with his Ultimate R. Against mordekaiser, As soon as Mordekaiser activates his W, disengaged as he will block the damage you inflict on him if you continue to fight him. Mordekaiser is quite still. If you keep the wave of minions closer to your side of the map, you will force him to extend for the farm. Then you can capitalize on it and get the help of your Jungler. Once Mordekaiser reaches level 6, his pressure of death in the way grows. Keep this in mind and be careful with your positioning when weak as he can try to catch you with his Ultimate R.