Alexios, Deimos of Kosmos

Trample
Alexios attacks each combat if able, can't be sacrificed, and can't attack its owner.
At the beginning of each player's upkeep, that player gains control of Alexios, untaps it, and puts a +1/+1 counter on it. It gains haste until end of turn.

Measure of Wickedness

At the beginning of your end step, sacrifice this enchantment and you lose 8 life.
Whenever another card is put into your graveyard from anywhere, target opponent gains control of this enchantment.

Contested Game Ball

Whenever you're dealt combat damage, the attacking player gains control of this artifact and untaps it.
{2}, {T}: Draw a card and put a point counter on this artifact. Then if it has five or more point counters on it, sacrifice it and create a Treasure token.

Path of Bravery

As long as your life total is greater than or equal to your starting life total, creatures you control get +1/+1.
Whenever one or more creatures you control attack, you gain life equal to the number of attacking creatures.