This data is collected from the articles deck lists in EDH Chamber.
Tempo is a way to describe decks focusing on heavy interaction with efficient mana usage. Tempo decks play a few threats early, and try to chip away opponents HP and resources. Tempo decks are not the fastest decks causing damage, and aim to dragging the game a bit longer, and preventing opponents plans with right timed removals.
Saboteur is an effect on a creature triggered whenever the creature deals combat damage to an opponent. Many saboteur creatures have evasion and can wreck havoc with their effects if unanswered.
Unblockable creatures often have strong evasion, like flying or fear, or they are simply unblockable. Highly evasive creatures tend to have lower power to balance the strong effect of free damage in combat and tend to have lower toughness too.
The ways to discard are plenty: cycling, rummaging, end steps discard phase, to name a few. Discard decks are built around triggers from discarding, like madness and synergizes well with reanimating.
White has many great support spells and permanents for +1/+1 counters theme. Counters theme is often combined with White-weenie or token strategy and turns the small creatures into a formidable force.
Voltron decks focus on commander damage or a few creatures and turns them into massive, protection-from-everything kind of creatures and finishing off the opponents in combat.
Lifegain is one of the the most popular themes in EDH. Multiple triggers to gain life and value received from the lifegain triggers are really fun to follow as a player. Often lifegain is combined with another theme, +1/+1 counters or creature tokens, as pure lifegain is often not powerful enough to win the game.
Combo decks are control heavy decks, running a heavy amount of card draw or tutors. If the decks get to assemble the combo pieces the game often ends in an infinite combo.
White has many great support spells and permanents for +1/+1 counters theme. Counters theme is often combined with White-weenie or token strategy and turns the small creatures into a formidable force.