Your Win Condition
Completely destroy him at the level six timer. You win the long trades easily once you have your ultimate and he loses his W block.
General Strategy
D-Blade, Ghost, and Flash. Play very passively and 'scared' 1-5. Do not take volatile trades or burn mana early. Let him push you in.
Trading Patterns
Play to conserve HP and mana 1-5. Try to bait his Q by running towards him and juking backwards. The second you hit level six, if you hit your axe and have Ghost/Flash available, he is dead.
Wave Management
Let him push you in during the early game. Maintain high HP leading up to level six.
Their Win Condition
Pantheon wins by poking you down 1-5 and getting a successful all-in with Ignite before you hit level six.
