You can Tribute 1 Warrior-Type monster to Special Summon this card from your hand. If you do, it gains ATK equal to the Tributed monster's original ATK.
You can Tribute a face-down Warrior for
"Turret Warrior", and it will still gain the appropriate ATK.
You can Tribute a Warrior-Type Token monster to Special Summon
"Turret Warrior", or a card like
"Embodiment of Apophis" that is currently a Warrior.
"Turret Warrior" still gains the appropriate ATK in these cases.
If you Tribute a Warrior with variable ATK, like
"Evil Hero Dark Gaia", the original ATK is treated as 0 so
"Turret Warrior" gains no bonus ATK.
Tributing a Warrior to Special Summon
"Turret Warrior" is not a cost; both the Tribute and the ATK increase are part of the effect.