So...
1)
Trigger will make invulnerable all units belong to pl. 11/12 when they stand on Black Bricks(example). So if unit leaves black bricks, he will be vulnerable.
2)
Spell.
This spell can be used only once. Makes your allies in 400 AoE invulnerable(but you can move), gaining 3 attack. Reduces enemy's attack by 2(1k range). Duration - 5 sec. Debuff is permament.
