Grasp of the Arknight

Once per Turn Action -

: Create a Runechant token. This ability costs an additional

to activate for each Runechant you control. Go again

Battleworn

Rulings

From the Arcane Rising release notes

The cost checks how many runechant tokens you have at the time you activate it, it does not include the runechant token you are about to make.
You cannot use this ability if you cannot pay the required costs. (You cannot sink resources into this if you cannot pay the full cost)

Keyword notes

Battleworn - Equipment that wear down after each time they are used to defend. If you defend with a card with Battleworn, put a -1{d} counter on it when the combat chain closes.

When you defend with a card it remains on the combat chain until the chain closes, therefore you cannot defend with an equipment multiple times on the same combat chain.
A -1 counter stays on the card until the card is destroyed or the game ends.
If the defense of a card that is defending is below zero, its defense value is considered to be zero.
When this card is destroyed, it is sent to your graveyard. (Not when it has 0)
When this card is destroyed, it is sent to your graveyard.
If the defense of a card that is defending is below zero, calculate as if its defense is zero.