Staff of the Mind Magus — ruling 1

Each of these artifacts cares about any land with the appropriate basic land type. For example, Staff of the Sun Magus’s ability triggers when any land with the subtype Plains enters the battlefield under your control, not just lands named Plains.

Staff of the Mind Magus — ruling 2

Most nonbasic lands don’t have basic land types, even if they produce colored mana. For example, Caves of Koilos is neither a Plains nor a Swamp. Having one enter the battlefield under your control won’t cause Staff of the Sun Magus’s ability to trigger.

Staff of the Mind Magus — ruling 3

If you cast a copy of a card that’s a certain color, the appropriate Staff’s ability will trigger. However, if you copy a spell on the stack without casting that copy, it will not.

Staff of the Mind Magus : règles, fonctionnement et interactions (MTG)

Staff of the Mind Magus is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Whenever you cast a blue spell or an Island you control enters, you gain 1 life.

How it works : Staff of the Mind Magus

Original English text — Wizards of the Coast / Scryfall

#1July 18, 2014· Wizards of the Coast
Each of these artifacts cares about any land with the appropriate basic land type. For example, Staff of the Sun Magus’s ability triggers when any land with the subtype Plains enters the battlefield under your control, not just lands named Plains.
No other card is named in this ruling.
#2July 18, 2014· Wizards of the Coast
Most nonbasic lands don’t have basic land types, even if they produce colored mana. For example, Caves of Koilos is neither a Plains nor a Swamp. Having one enter the battlefield under your control won’t cause Staff of the Sun Magus’s ability to trigger.
No other card is named in this ruling.
#3July 18, 2014· Wizards of the Coast
If you cast a copy of a card that’s a certain color, the appropriate Staff’s ability will trigger. However, if you copy a spell on the stack without casting that copy, it will not.
No other card is named in this ruling.