msem-instigator

Whenever Arena Challenger deals damage to a creature, upgrade it. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• First strike
• Prowess

Converge — Gain control of up to X target creatures with total mana value X or less, where X is the number of colors of mana spent to cast Alive and on Top.

Nonenchantment spells cost {1} more to cast.
Whenever you cast an enchantment spell, you gain 1 life and draw a card.

[+2]: Exile another target permanent, then return it to the battlefield under its owner's control.
[–2]: Gain control of target creature unless its controller pays its mana cost.
[–5]: You get an emblem with “If a nonland permanent would enter and it wasn't cast, it you control enters instead.”

Target creature gets -3/-3 until end of turn. You gain 3 life.

If you would put one or more counters on a creature you control or on yourself, put that many plus one of each of those kinds of counters on that creature or player instead.
{2}{G}{U}, Sacrifice Triton's Invocation: Draw cards equal to the greatest number of counters among creatures you control and yourself.

Destroy target artifact or enchantment. Its controller gains 4 life.

At the beginning of your end step, put a creature card that's exiled with this enchantment onto the battlefield under your control. That creature becomes a 1/1 Spirit creature in addition to its other types and gains flying and “If this creature would die, put it on the bottom of its owner's library instead.”

Flash
Flying
If an effect an opponent controls would cause them to take an extra turn, you take an extra turn instead.
{G}{U}: Return another creature you control to its owner's hand. Activate this ability only once each turn.

Flying, double strike

{2}{B}, Exile Lizhao's Soulblade from your graveyard: Return target creature card from your graveyard to your hand. Activate only as a sorcery.

Target player discards a card.
Monument {1}{B} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Vigilance, trample
Pay 3 life: You choose if and how target creature attacks or blocks this turn. You choose before its controller declares other attackers or blockers. Activate only once each turn.

Prevent all combat damage that would be dealt to and dealt by creatures this turn.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
At the beginning of your end step, if an opponent is cursed, surveil 2.

Enchant creature
Enchanted creature gets +2/+0.
{2}{B}, Exile Hold Me Down from your graveyard: Return target creature card from your graveyard to your hand.

Enchant creature
Enchanted creature has lifelink and protection from its colors. This effect doesn't remove Shimmerhold. (This permanent can't be targeted, dealt damage, enchanted, or equipped by anything its color.)

For each nontoken enchantment you control, conjure a duplicate of it into your hand. Until the end of your next turn, you have no maximum hand size.
Exile Root Duplication.

Counter target spell. Spells its controller casts cost {2} more to cast this turn.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
{1}{U}, Discard Lusterwing Owl: Return target enchantment to its owner's hand.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you cast your second spell each turn, add a quest counter.
1 — Exile the top card of your library. You may play that card until the end of your next turn.
2 — The second spell you cast during your next turn cost {1} less to cast.
3 — You may cast target instant or sorcery card from your graveyard this turn. When you do, copy it. You may choose new targets for the copy.

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only during an opponent's turn.