The difference between Debuff and Renew

When used as verbs, debuff means to make a character or unit weaker, whereas renew means to make (something) new again.

Debuff is also noun with the meaning: an effect that makes a game character weaker.

check bellow for the other definitions of Debuff and Renew

Debuff as a noun (RPG, video games):

An effect that makes a game character weaker; a negative status effect.

Debuff as a verb (RPG, video games):

To make a character or unit weaker.

Renew as a verb (transitive):

To make (something) new again; to restore to freshness or original condition.
Renew as a verb (transitive):

To replace (something which has broken etc.); to replenish (something which has been exhausted), to keep up a required supply of.
Renew as a verb (theology):

To make new spiritually; to regenerate.
Renew as a verb (now, _, rare, intransitive):

To become new, or as new; to revive.
Renew as a verb (transitive):

To begin again; to recommence.
Renew as a verb (rare):

To repeat.
Renew as a verb (transitive, intransitive):

To extend a period of loan, especially a library book that is due to be returned.

Examples:

"I'd like to renew these three books.&emsp; nowrap Did you know that you can renew online?"