Equipped creature gets +1/+1 and has
mentorMentor is a triggered ability. “Mentor” means “Whenever this creature attacks, put a +1/+1 counter on target attacking creature with power less than this creature’s power.”
If a creature has multiple instances of mentor, each triggers separately.
An ability that triggers whenever a creature mentors another creature triggers whenever a mentor ability whose source is the first creature and whose target is the second creature resolves. (CR 702.134). (Whenever it attacks, put a +1/+1
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on target attacking creature with lesser power.)
Whenever equipped creature mentors a creature, put a shield
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on that creature. (If that creature would be dealt damage or destroyed, remove a shield
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) from it instead.)
EquipEquip is an activated ability of Equipment cards. “Equip [cost]” means “[Cost]: Attach this permanent to target creature you control. Activate only as a sorcery.”
For more information about Equipment, see rule 301, “Artifacts.”
Equip abilities may further restrict what creatures may be chosen as legal targets. Such restrictions usually appear in the form “Equip [quality]” or “Equip [quality] creature.” These equip abilities may legally target only a creature that’s controlled by the player activating the ability and that has the chosen quality. Additional restrictions for an equip ability don’t restrict what the Equipment may be attached to.
If a permanent has multiple equip abilities, any of its equip abilities may be activated.
“Equip planeswalker” is a variant of the equip ability. “Equip planeswalker [cost]” means “[Cost]: Attach this permanent to target planeswalker you control as though that planeswalker were a creature. Activate only as a sorcery.” (CR 702.6)