@ Maruno-
Cool traps. I love GS the archfiend and Unreal tournanment. GS for the fact that its an archfiend monster with good stats that gets special summon and is trap card. I would have a field day with Unreal Tournanment. I mean swarming and the chance to gain LP? That just screams STAPLE in an archfiend deck. That deck type really needs a card like this to get each archfiend on the field as soon as possible.
And if we were using the archfiend I made, oh, I know just what five archfiends I would summon with this.
You should probably put a limit on this of one. I mean, monsters can be special summon from anywhere othe than RFP pile. Think of some of strongest monsters (by effect) right now that would benefit from that and are hard to put on the field:
The Creator, DM of Chaos, Sacred Phoenix, Envoys (if they summoned properly first),
A person could get out a annoying lock to break like
Jinzo+
Spell Canceller+
Patrician of Darkness+ Ha Des+End of Anubis(stop graveyard effects) or Kycoo (to stop Envoys from showing up) or
Spirit Reaper (when they hit something over 2400) or another variant fifth choice. Sure Tribe can take care of that but would you discard that many cards?
Also, what happens when before players end up with an equal amount of monsters?
Since the card prevents players from playing any other spells/traps, they simply play everything else first then this. Maybe put in a
Cold Wave-like restriction which will force them to play it at the very beginining of Main Phase 1 before they can play anything else.