You may exert this creature as it attacks. When you do, it can't be blocked this turn and you scry 1. (An exerted creature won't untap during your next untap step. To scry 1, look at the top card of your library. You may put that card on the bottom.)

Return all land cards from your graveyard to the battlefield tapped.

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following abilities until end of turn.)
Deathtouch
Whenever this creature deals combat damage to a player or battle, return target creature card from your graveyard to the battlefield.

: Add .
, , Sacrifice a land: Destroy target nonbasic land.

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When this Aura is put into a graveyard from the battlefield, return it to its owner's hand.

Destroy target nonland permanent and all other permanents with the same name as that permanent.

(: Add .)

: Add .
Whenever a legendary creature you control enters, you may have The Irencrag become a legendary Equipment artifact named Everflame, Heroes' Legacy. If you do, it gains equip and "Equipped creature gets +3/+3" and loses all other abilities.

When this creature enters, sacrifice it unless you sacrifice three Forests.

Flying
Whenever Zur attacks, you may search your library for an enchantment card with mana value 3 or less, put it onto the battlefield, then shuffle.

Emerge (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When this creature enters, create a 2/2 white Alien creature token. If this creature's emerge cost was paid, instead create X of those tokens, where X is the sacrificed creature's toughness.

Deathtouch
Whenever Radioactive Man deals combat damage to a player, that player loses half their life, rounded up.

, Sacrifice two creatures: Return target creature card from your graveyard to the battlefield.

Populate. Creatures you control gain indestructible until end of turn. (To populate, create a token that's a copy of a creature token you control.)

: Target creature gets +1/+1 until end of turn.

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
: Add or .

At the beginning of your upkeep, you may exile Cosima. If you do, it gains "Whenever a land you control enters, if Cosima is exiled, you may put a voyage counter on it. If you don't, return Cosima to the battlefield with X +1/+1 counters on it and draw X cards, where X is the number of voyage counters on it."

, : Draw a card, then discard a card. Create a Treasure token. (It's an artifact with ", Sacrifice this token: Add one mana of any color.")

Lava Axe deals 5 damage to target player or planeswalker.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for or one mana of that creature's color.)
For each player, you choose a creature that player controls. Then each player sacrifices all other creatures they control that don't share a creature type with the chosen creature they control.