remoralise
To raise a person's morale after it has been previously lowered, generally with the intent of lowering it again immediately after. To lift someone up so they have farther to fall back down. The opposite of demoralise.
henry: Why are you losing on purpose?
tom: I am going to remoralise him so when I win he will be more demoralised.
tom: I am going to remoralise him so when I win he will be more demoralised.