Aang, the War Ender

Avatar state — If you control two or more Avatars,
choose one of them, and the rest are put into
their owners' graveyards. At the beginning of your
upkeep, you may pay {w}{u}{b}{r}{g}. If you do, Aang,
the War Ender gains all activated abilities of all
Avatars in all graveyards.
{1}{w}{u}: Put a bending counter on up to one
target creature. Creatures with bending counters
lose all abilities and have base power and
toughness 1/1.