MTG Mono Red Aggro Deck by Grey Heron

Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it. When this creature dies, it deals damage equal to its power to each opponent.

{1}{R}: If Kellan is a Scout, it becomes a Human Faerie Detective and gains "Whenever Kellan deals combat damage to a player, exile the top card of your library. You may play that card this turn." {2}{R}: If Kellan is a Detective, it becomes a 3/2 Human Faerie Rogue and gains double strike.

Haste Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Haste Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, exile the top card of your library. Until end of turn, you may play that card.

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.) At the beginning of combat on your turn, target Mouse you control gains your choice of double strike or trample until end of turn.

Flying, haste Whenever you cast a noncreature spell, this creature gets +2/+0 until end of turn. Plot {1}{R} (You may pay {1}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Haste Whenever this creature is dealt damage, it deals that much damage to any other target. If a player is dealt damage this way, they can't gain life for the rest of the game.

Kicker {4} (You may pay an additional {4} as you cast this spell.) Burst Lightning deals 2 damage to any target. If this spell was kicked, it deals 4 damage instead.

Target creature gets +2/+0 until end of turn. Create a Monster Role token attached to it. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample.)

Target creature gets +3/+0 until end of turn. When it dies this turn, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Lightning Strike deals 3 damage to any target.

This spell costs {1} less to cast for each creature that attacked this turn. Witchstalker Frenzy deals 5 damage to target creature.

({T}: Add {R}.)

{T}: Add {C}. {T}: Add {R}. Spend this mana only to cast a creature spell. {R}, {T}: Target Lizard, Mouse, Otter, or Raccoon you control gets +1/+0 and gains haste until end of turn. Activate only as a sorcery.