Exuberant Wolfbear

• WWizards of the Coast2020-04-17
  Official Ruling
  The Human’s new base power and toughness are set to Exuberant Wolfbear’s actual power and toughness, not just its base power and toughness. If Exuberant Wolfbear’s power or toughness changes later in the turn, the Human isn’t affected.
• WWizards of the Coast2020-04-17
  Official Ruling
  Exuberant Wolfbear’s power and toughness are unaffected when the target Human takes on those values.
• WWizards of the Coast2020-04-17
  Official Ruling
  Any effects that modify the Human’s power and/or toughness without setting them to a specific number or value will apply after its base power and toughness are set, regardless of the order in which those effects were created. The same is true of counters that modify its power and toughness.
• WWizards of the Coast2020-04-17
  Official Ruling
  If Exuberant Wolfbear leaves the battlefield while its triggered ability is on the stack, use its power and toughness as it last existed on the battlefield to determine the Human’s new base power and toughness.
• WWizards of the Coast2020-04-17
  Official Ruling
  You choose whether the Human’s base power and toughness change as the ability resolves, not as the ability is put onto the stack.

Rulings via Scryfall