[2020] Help with Gideon please

I honestly dont know what to say, the fight takes so long that no matter how well im doing, i get that RNG where he teleports right behind me and 1 taps me at some point during the fight.

Im a lv 21 mage, 1k gs, and lionheart. im using pan of blades and elixir of blades, with purple pot 3s and pie regen.

Please, somebody tell me theres a way to cheese him; Ive beaten every Dark Souls game, but this boss takes too long and all it takes as a glass cannon mage is one sh*tty teleport RNG and im done. Any advice is sincerely appreciated, im about to just call it quits on this game, as i dont feel like mindlessly grinding another 10 levels with no story progression.

edit: Got it, just bought blue restore pots, thanks guys