Twinblade Paladin

In a Two-Headed Giant game, life gained by your teammate won't cause Twinblade Paladin's first ability to trigger, even though it caused your team's life total to increase.

If Twinblade Paladin gains double strike after combat damage has already been dealt (most likely because a creature with lifelink dealt combat damage), Twinblade Paladin will deal only regular combat damage.

Each creature with lifelink dealing combat damage causes a separate life-gaining event. For example, if two creatures you control with lifelink deal combat damage at the same time, Twinblade Paladin's first ability will trigger twice. However, if a single creature you control with lifelink deals combat damage to multiple creatures, players, planeswalkers, and/or battles at the same time (perhaps because it has trample or was blocked by more than one creature), the ability will trigger only once.

In a Two-Headed Giant game, life gained by your teammate won't cause the first ability to trigger, even though it caused your team's life total to increase.

Twinblade Paladin's first ability triggers just once for each life-gaining event, whether it's 1 life from Dazzling Angel or 4 life from Apothecary Stomper.