Arena legendary cards problem

I never win aganist these legendary cards, I am playing arena 8 hours in a day.
Druid 5-5 legendary- random 10 legendary and they are 1 mana(everytime what you need not random)
Druid alextrazsa legendary- discover unlimited 4 mana less OP dragons
Mage 2 mana legendary spell- discover unlimited card(Finale return to your hand)
Mage excavite discover titan card most OP excavite in arena
new 6-6 legendary pirate
new 3-3 nozdormu dragon (2) cost spell summon three 2 mana minion (upgrade each turn)
These cards are game breaker

For the balance of arena “random discover legendary cards” mechanics may disable.