MH3 is one of the highest-power Magic sets from the last few years
Creatures (6) Arboreal Grazer x4 Subtlety x2 Instants (18) Lightning Bolt x3 Counterspell x4 Planar Genesis x4 Expansion / Explosion x3 Nexus of Fate x4 Sorcery (4) Gates Ablaze x4 Enchantments (7) Guild Summit x4 Wilderness Reclamation x3 Lands (25) Azorius Guildgate Breeding Pool x2 Gruul Guildgate x4 Island Izzet Guildgate x4 Misty Rainforest x2 Scalding Tarn x2 Simic Guildgate x4 Steam Vents x2 Thran Portal x3 Sideboard (15) Consign to Memory Haywire Mite x2 Spell Pierce x2 Swan Song Damping Sphere x2 Dismember x2 Gatebreaker Ram x4 Force of Vigor I won't pretend that this is the most competitive Modern deck in the world, but it's a riff on a deck I loved playing in the Standard, and it gives you a pretty good idea of how a gates deck wants to play
Individually these effects are marginal: but combined they form a card that was so good, many non-red blue base decks started playing red just to get it (plus Flametongue Kavu, to be perfectly fair)
Tired of beefy blockers stopping your Elves
The three tiers each have a flavor word for additional well, flavor, but these words have no effect on gameplay
One option is to use the cards ability for card draw and discarding in conjunction with other characters that benefit from card draw and discarding such as Gustav The Giant, Terror of the Kingdom, Jafar, Striking Illusionist and Maleficent, Mistress of All Evil