When Cloud enters, search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
As long as Cloud is equipped, if an ability of Cloud or an Equipment attached to it triggers, that ability triggers an additional time.

When Peter Parker enters, create a 2/1 green Spider creature token with reach.
: Transform Peter Parker. Activate only as a sorcery.

+2: Each player draws a card.
−1: Target player draws a card.
−10: Target player mills twenty cards.

Flying
Whenever Kaalia attacks an opponent, you may put an Angel, Demon, or Dragon creature card from your hand onto the battlefield tapped and attacking that opponent.

+1: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.
−3: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of Swamps you control.
−6: You get an emblem with "Swamps you control have ': Add .'"

+1: Draw a card. Target player mills a card.
0: Target player mills ten cards.
−7: Any number of target players each draw twenty cards.

+1: Distribute three +1/+1 counters among one, two, or three target creatures you control.
+1: Look at the top four cards of your library. You may reveal an Aura, creature, or planeswalker card from among them and put it into your hand. Put the rest on the bottom of your library in any order.
−8: You gain 100 life.

During your turn, as long as Cloud is equipped, it has double strike and indestructible. (This creature deals both first-strike and regular combat damage. Damage and effects that say "destroy" don't destroy this creature.)
Equip abilities you activate that target Cloud cost less to activate.

Vigilance (Attacking doesn't cause this creature to tap.)
When Sephiroth enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, put a +1/+1 counter on Sephiroth.

Vigilance, trample (Attacking doesn't cause this creature to tap. He can deal excess combat damage to the player he's attacking.)
Whenever Spider-Man enters or attacks, put a +1/+1 counter on each other creature you control. Those creatures gain trample until end of turn.

+3: Destroy target noncreature permanent.
−2: Gain control of target creature.
−9: Nicol Bolas deals 7 damage to target player or planeswalker. That player or that planeswalker's controller discards seven cards, then sacrifices seven permanents of their choice.